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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Travel Decision Survey - San Francisco - 2012

On behalf of the San Francisco Municipal Transportation Agency (SFMTA), Corey, Canapary & Galanis undertook a Travel Decision Survey within the City and County of San Francisco, as well the eight surrounding Bay Area counties of Alameda, Contra Costa, San Mateo, Marin, Santa Clara, Napa, Sonoma, and Solano. The primary goals of this study were to accurately assess mode share for trips within San Francisco (including trips to or from San Francisco, but excluding through trips) among city residents and residents of other Bay Area counties; provide additional trip details, including trip purpose information for each trip in the mode-share question series; and use the mode-share percentages collected on this survey in conjunction with total trip estimates provided by SFMTA to project the number of trips by mode on an average day in San Francisco.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Travel Decision Survey - San Francisco - 2013

On behalf of the San Francisco Municipal Transportation Agency (SFMTA), Corey, Canapary & Galanis undertook a Travel Decision Survey within the City and County of San Francisco, as well as the eight surrounding Bay Area counties of Alameda, Contra Costa, San Mateo, Marin, Santa Clara, Napa, Sonoma, and Solano. The primary goals of this study were to: 1. Assess percent mode share for travel in San Francisco for evaluation of the SFMTA Strategic Objective 2.3: Mode Share target of 50% non-private auto travel by FY 2018 with a 95% confidence level and margin of error ±5% or less. 2. Evaluate the above statement based on number of trips to, from, and within San Francisco by Bay Area residents. Trips by visitors to the Bay Area and for commercial purposes are not included. 3. Provide additional trip details, including trip purpose for each trip in the mode-share question series. 4. Collect demographic data on the population of Bay Area residents who travel to, from, and within San Francisco. 5. Collect data on travel behavior and opinions that support other SFMTA strategy and project evaluation needs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Travel Decision Survey - San Francisco - 2014

On behalf of the San Francisco Municipal Transportation Agency (SFMTA), Corey, Canapary & Galanis undertook a Travel Decision Survey within the City and County of San Francisco, as well as the eight surrounding Bay Area counties of Alameda, Contra Costa, San Mateo, Marin, Santa Clara, Napa, Sonoma, and Solano. The primary goals of this study were to: 1. Assess percent mode share for travel in San Francisco for evaluation of the SFMTA Strategic Objective 2.3: Mode Share target of 50% non-private auto travel by FY 2018 with a 95% confidence level and margin of error ±5% or less. 2. Evaluate the above statement based on number of trips to, from, and within San Francisco by Bay Area residents. Trips by visitors to the Bay Area and for commercial purposes are not included. 3. Provide additional trip details, including trip purpose for each trip in the mode-share question series. 4. Collect demographic data on the population of Bay Area residents who travel to, from, and within San Francisco. 5. Collect data on travel behavior and opinions that support other SFMTA strategy and project evaluation needs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Travel Decision Survey - San Francisco - 2015

On behalf of the San Francisco Municipal Transportation Agency (SFMTA), Corey, Canapary & Galanis undertook a Travel Decision Survey within the City and County of San Francisco, as well as the eight surrounding Bay Area counties of Alameda, Contra Costa, San Mateo, Marin, Santa Clara, Napa, Sonoma, and Solano. The primary goals of this study were to: 1. Assess percent mode share for travel in San Francisco for evaluation of the SFMTA Strategic Objective 2.3: Mode Share target of 50% non-private auto travel by FY 2018 with a 95% confidence level and margin of error ±5% or less. 2. Evaluate the above statement based on number of trips to, from, and within San Francisco by Bay Area residents. Trips by visitors to the Bay Area and for commercial purposes are not included. 3. Provide additional trip details, including trip purpose for each trip in the mode-share question series. 4. Collect demographic data on the population of Bay Area residents who travel to, from, and within San Francisco. 5. Collect data on travel behavior and opinions that support other SFMTA strategy and project evaluation needs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Travel Decision Survey - San Francisco - 2017

On behalf of the San Francisco Municipal Transportation Agency (SFMTA), Corey, Canapary & Galanis undertook a Travel Decision Survey within the City and County of San Francisco, as well as the eight surrounding Bay Area counties of Alameda, Contra Costa, San Mateo, Marin, Santa Clara, Napa, Sonoma, and Solano. The primary goals of this study were to: 1. Assess percent mode share for travel in San Francisco for evaluation of the SFMTA Strategic Objective 2.3: Mode Share target of 50% non-private auto travel by FY 2018 with a 95% confidence level and margin of error ±5% or less. 2. Evaluate the above statement based on number of trips to, from, and within San Francisco by Bay Area residents. Trips by visitors to the Bay Area and for commercial purposes are not included. 3. Provide additional trip details, including trip purpose for each trip in the mode-share question series. 4. Collect demographic data on the population of Bay Area residents who travel to, from, and within San Francisco. 5. Collect data on travel behavior and opinions that support other SFMTA strategy and project evaluation needs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

Riders’ perceptions towards transit bus electrification: Evidence from Salt Lake City, Utah

While battery electric buses (BEBs) can lead to energy savings and reduced emissions, BEB adoption is developing slowly. Although BEBs offer quieter operations, better acceleration, and no smell of diesel or gas fumes, little focus has been placed on the user’s perspective. Here, this study investigates bus riders’ preferences toward BEBs. To achieve these objectives, a survey was designed and administered to solicit riders’ typical travel behaviors and patterns as well as preferences and opinions about BEBs’ performance in terms of emissions and noise. Statistical analysis showed that several factors influence rider perceptions towards transit bus electrification that include trip purpose, attitudes towards environmental issues and environmental impacts of BEBs, and certain non-instrumental ride factors such as ride comfort and social image. A better understanding of the importance of electrification to transit riders can help transit service providers adjust their marketing decisions and their systemwide operations to accommodate preferences towards BEBs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

An Anomalous Electron Configuration Among 3d Transition Metal Atoms

Physical properties of materials are mainly determined by valence electron configurations, where different valence shells would induce divergent phenomena. In compounds containing Sc 2+ , 3d electron occupancy is expected, same as other transition metal atoms like Ti 3+ . But this situation still awaits experimental verification. In this work, we selected ScS to measure the valence electron density and orbital population of Sc2+ through delicate quantitative convergent-beam electron diffraction. Though the [Ar]3d 1 configuration is confirmed in ionic Sc 2+ , the unintuitive occupation of 4s orbital is concluded with the absence of 3d orbital features around Sc-atom sites and nearly bare population of t2g orbital. It should be the first time to report this special electron configuration in a transition metal compound, in which 4s rather than 3d orbital is preferred. Our findings reveal the distinct behavior of Sc, and probable ways to modulate material properties by controlling electron orbitals.

36 MATERIALS SCIENCE↗
DOE OSTI2026

1990 CATS Household Travel Survey

The Chicago Area Transportation Study (CATS) 1990 Household Travel Survey was a self-administered mail-out mail-back survey. The purpose of the study was to update existing data on travel patterns and characteristics of Chicago residents. CATS surveyed the region on a county-by-county basis with the Chicago Central Business District in collaboration with the Urban Transportation Center of the University of Illinois. The study gathered demographic and travel behavior data from residents of northeastern Illinois who were 14 years old or older. 19,314 households participated in the survey. The study focused on non-work travel by motorized vehicle and by foot, and residents recorded their trips on a single travel day. Transportation-related variables include trip origin and destination, trip purpose, travel time, mode of travel used, vehicle occupancy, and walking distance (if that transit mode was involved).

1Hz data↗
DOE OSTI2026

2008 NIRPC Household Travel Inventory

The Northwestern Indiana Regional Planning Commission (NIRPC) Household Travel Inventory, also sponsored by the Indiana Department of Transportation, is a comprehensive study of the demographic and travel of residents of Lake, Porter, and La Porte counties in northwest Indiana. The primary objective of the study was to provide data for the continued development and refinement of the Indiana regional travel demand forecast models. 3,838 households from northwest Indiana participated in the survey, which entailed the collection of activity and travel information for all household members regardless of age during a randomly assigned 24- or 48-hour period. NIRPC travel survey data provided the information required on base-year daily trips made by study area residents to the Chicago CBD. This travel market is treated separately because of the importance of transit for its travelers.

1Hz data↗
DOE OSTI2025

Resident Tolerance to Transitional Temperature Deviation in Smart Communities

Choosing the right HVAC system or the right algorithm of implementing demand response may create significant energy and environmental gains while maintaining resident comfort. But these questions are closely related to the concept of user comfort, which in turn requires a reasonable fit between user preferences and temperature setpoints. While setting the temperature right is a well-researched question, systems in transition from one setpoint to another are currently not thoroughly addressed in research. But how tolerant the residents really are if a system spends a large share of time outside of the comfort setpoint. This study gives some early insights on how the deviation of temperature from the setpoint affect perceived resident comfort. We use two weeks of data for a smart neighborhood located in Atlanta, GA. We find that the system spends 20% - 50% of time deviating from the setpoint by more than 1℉. However, we do not find that increasing deviations cause resident complaints or increasing overrides.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Identifying Strain Stacking Boundaries between Multiphase Domains in Atomically Thin Two-Dimensional Magnets

Stacking engineering of van der Waals materials is an important strategy to control the materials’ properties, such as electronic correlations, ferroelectricity, and layer-dependent two-dimensional magnetism. A timely testbed for the study of the latter is atomically thin chromium trihalides (CrX 3 , X = Cl, Br, I). Notably, by understanding the sliding mechanism between different stacking sequences, control of the stacking arrangement, and thus magnetic properties in CrX 3 , can be achieved. Such insight, however, is currently lacking. Here, in this study, advanced electron microscopy methods are used to identify multiple stacking sequences corresponding to different bulk phases in atomically thin CrX 3 (X = Cl and Br) down to bilayer thickness and with lateral domain sizes as small as tens of nanometers. Indications of nanometer scale transitions and interactions at the stacking boundaries are found, including a universally preferred sliding direction that is consistent with density functional theory calculations and the strain fields at lateral heterostructure boundaries. This study demonstrates the necessity to consider local stacking structures when interpreting averaged magnetic properties measured with macroscale probes. Additionally, the preferred sliding direction insight from this study provides a strategy to control stacking sequence in atomically thin CrX 3 samples during the exfoliation and sample fabrication process.

DFT calculations↗
DOE OSTI2024

An Adsorptive Membrane Platform for Precision Ion Separation: Membrane Design and First‐Principles Studies

One of the key challenges in separation science is the lack of precise ion separation methods and mechanistic understanding crucial for efficiently recovering critical materials from complex aqueous matrices. Herein, first-principles electronic structure calculations and in situ Raman spectroscopy are studied to elucidate the factors governing ion discrimination in an adsorptive membrane specifically designed for transition metal ion separation. Density functional theory calculations and in situ Raman data jointly reveal the thermodynamically favorable binding preferences and detailed adsorption mechanisms for competing ions. How membrane binding preferences correlate with the electronic properties of ligands is explored, such as orbital hybridization and electron localization. The findings underscore the importance of the phenolate group in oxime ligands for achieving high selectivity among competing transition metal ions. In-depth understanding on which specific atomistic site within the microenvironment of metal-ligand binding pockets governs the ion discrimination behaviors of the host will build a solid foundation to guide the rational design of next-generation materials for precision separation essential for energy technologies and environment remediation. In tandem, synthetic controllability is demonstrated to transform 3D micrometer-scale crystals to a 2D crystalline selective layer in membranes, paving the way for more precise and sustainable advances in separation science.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Dynamically preferred state with strong electronic fluctuations from electrochemical synthesis of sodium manganate

Electrochemical (de)intercalation is a delicate method to precisely control the alkaline ion composition in alkaline transition metal oxides. Because of complicated interactions, metal charge ordering patterns can form spontaneously at special fractional alkaline compositions and orderings. In this study, we show that this elegant electrochemical process can create dynamically preferred structures in an anharmonic energy landscape that conventional syntheses and computations can rarely visit. Specifically, electrochemically prepared Na 1/2 MnO 2 ordering exhibits abnormal structure distortions, charge orderings, and dynamical activities. Strong magnetic fluctuations and lattice dynamics are observed in an unusually wide temperature range in Na 1/2 MnO 2 , which distinguishes it from all other Na x MnO 2 at higher or lower Na compositions. The results emphasize the unique opportunity of using electrochemical processes to design and create novel quantum states with strongly coupled and mutually enhanced electronic and lattice fluctuations, likely through a special dynamic charge flux functional, as suggested by our computational investigations.

25 ENERGY STORAGE↗
DOE OSTI2026

1990 The Twin Cities Metropolitan Area Travel Behavior Inventory

The Twin Cities Metropolitan Area 1990 Travel Behavior Inventory, or home interview survey, was conducted by Twin Cities Metropolitan Council—Saint Paul to document how Twin Cities residents use the streets, highways, and transit services in the region. The survey collected demographic, socioeconomic, and travel data for 9,476 households. Respondents were asked to record their travel and activities for a 24-hour period, in which 98,535 trips were documented. In addition to the home interview survey, the study included an establishment survey, a transit survey, external station traffic counts, and an external station origin/destination survey.

1Hz data↗
DOE OSTI2021

Green’s functions on a renormalized lattice: An improved method for the integer quantum Hall transition

Highlights: • Speed up of numerical calculations by exact renormalization group steps. • Practical approach to handle delicate scaling analysis. • Absence of evidence to prefer marginal corrections over power-law corrections. We introduce a performance-optimized method to simulate localization problems on bipartite tight-binding lattices. It combines an exact renormalization group step to reduce the sparseness of the original problem with the recursive Green’s function method. We apply this framework to investigate the critical behavior of the integer quantum Hall transition of a tight-binding Hamiltonian defined on a simple square lattice. In addition, we employ an improved scaling analysis that includes two irrelevant exponents to characterize the shift of the critical energy as well as the corrections to the dimensionless Lyapunov exponent. We compare our findings with the results of a conventional implementation of the recursive Green’s function method, and we put them into broader perspective in view of recent development in this field.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2023

Crystallographic texture formation in Fe-9wt%Si alloy during deformation and phase transition at high pressure

SUMMARY The seismic anisotropy of the Earth's solid inner core has been the topic of much research. It could be explained by the crystallographic preferred orientation (CPO) developing during convection. The likely phase is hexagonal close-packed iron (hcp), alloyed with nickel and some lighter elements. Here we use high energy synchrotron X-rays to study CPO in Fe-9wt%Si, uniaxially compressed in a diamond anvil cell in radial geometry. The experiments reveal that strong preferred orientation forms in the low-pressure body-centred cubic (bcc) phase that appears to be softer than pure iron. CPO is attributed to dominant {110}<111> slip. The onset of the bcc→hcp transition occurs at a pressure of ≈15 GPa, and the alloy remains in a two phase bcc + hcp state up to 40 GPa. The hcp phase forms first with a distinct {11$\bar{2}$0} maximum perpendicular to compression. Modelling shows that this is a transformation texture, which can be described by Burgers orientation relationship with variant selection. Experimental results suggest that bcc grains oriented with <100> parallel to compression transform into hcp first. The CPO of the hcp changes only slowly during further pressure and deviatoric stress increase at ambient temperature. After heating to 1600 K, a change in the hcp CPO is observed with alignment of (0001) planes perpendicular to compression that can be interpreted as dominant (0001)<11$\bar{2}$0> slip, combined with {10$\bar{1}$2}<$\bar{1}$011> mechanical twinning, which is similar to the deformation modes suggested previously for pure hcp iron at inner core conditions.

Vasin, Roman N.↗
DOE OSTI2022

Mineralogy, fabric and deformation domains in D" across the southwestern border of the African LLSVP

Recent advances in seismic anisotropy studies that jointly use reflections and shear wave splitting have proven to place tight constraints on the plausible anisotropic and deformation scenarios in the D" region. We apply this novel methodology to a large area of the D" region beneath the South Atlantic, in proximity to and within the African large low seismic velocity province (LLSVP). This area of the mantle is characterized by a transition from fast to slow seismic velocity anomalies and it is thought to be the location of deep-seated plumes responsible for hotspot volcanism. Attempting to probe mantle composition and deformation along the LLSVP borders may provide key information on mantle dynamics. By analysing seismic phases sampling this region, we detect a D" discontinuity over a large area beneath the South Atlantic, with inferred depth ranges ~170 to ~240 km above the core–mantle boundary. We find evidence for a D" reflector within the area of the LLSVP. Shear wave splitting observations suggest that anisotropy is present in this region of the mantle, in agreement with previous studies that partially sampled this region. We model the observations considering lattice- and shape-preferred orientation of materials expected in the D" region. A regional variation of mineralogy, phase transition boundaries, and deformation direction is required to explain the data. We infer two distinct domains of mineralogy and deformation: aligned post-perovskite outside the LLSVP and aligned bridgmanite within the LLSVP. Finally, the scenario depicted by this study agrees well with the current hypotheses for the composition of the LLSVP and with the prevalence of vertical deformation directions expected to occur along the LLSVPs borders.

58 GEOSCIENCES↗
DOE OSTI2026

1997 Broward Travel Characteristics Study

The Broward Travel Characteristics Study was initiated in February 1996 to identify localized socioeconomic and travel characteristics that could be used to improve the travel forecasting accuracy of the Florida Standard Urban Transportation Model System for Broward County. The survey recruited 2,625 households. Of these, 880 households completed the survey, indicating household demographic and socioeconomic characteristics (household verification survey). 33% of the households also completed a Direct Utility Assessment survey used to estimate the propensity for using transit. A total of 1,651 daily trips were extracted from the travel log survey over a 2-week period.

1Hz data↗