45 research outputs found
Case studies of job access and reverse commute program: 2009-2010
This report presents perceptual, mobility and employment outcomes self-reported by 573 users
of 26 transportation services funded by the Job Access and Reverse Commute (JARC) program.
The respondents were predominantly low income with 42 percent reporting 2008 personal
incomes less than 20,000 or less for the
same year. Nearly half the respondents have no household vehicles. Nearly three in five
respondents reported that their travel has become reliable and convenient after using the
services. Workers using the services have benefitted from overall reductions in the cost of
commuting to work.
Close to 94 percent rated the service as being important or very important in keeping their jobs.
Respondents also self-reported that the services allowed them to access a job with better pay or
better working conditions, and to improve their skills. Both median hourly wages and median
weekly earnings are reported to have increased since using the service for those workers who
use the service to commute to work and were employed in the one-month period prior to
starting use of the service. Alternative reasons may exist for these wage changes, including
overall changes in the economic conditions of the locations where the services operate, as well
as changes in the personal conditions of the workers that are unrelated to the JARC program in
the period between starting use of the service and the time of the survey, such as graduation
from job-training or school, residential relocation and so on.
Because of the lack of a probability sample of services, the results cannot be generalized to the
entire JARC program. Detailed case studies of the 26 services yield insights into the types of
benefits that are being provided overall in these cases and the planning and programmatic
environment within which they operate
Case studies of job access and reverse commute program: 2009-2010
This report presents perceptual, mobility and employment outcomes self-reported by 573 users
of 26 transportation services funded by the Job Access and Reverse Commute (JARC) program.
The respondents were predominantly low income with 42 percent reporting 2008 personal
incomes less than 20,000 or less for the
same year. Nearly half the respondents have no household vehicles. Nearly three in five
respondents reported that their travel has become reliable and convenient after using the
services. Workers using the services have benefitted from overall reductions in the cost of
commuting to work.
Close to 94 percent rated the service as being important or very important in keeping their jobs.
Respondents also self-reported that the services allowed them to access a job with better pay or
better working conditions, and to improve their skills. Both median hourly wages and median
weekly earnings are reported to have increased since using the service for those workers who
use the service to commute to work and were employed in the one-month period prior to
starting use of the service. Alternative reasons may exist for these wage changes, including
overall changes in the economic conditions of the locations where the services operate, as well
as changes in the personal conditions of the workers that are unrelated to the JARC program in
the period between starting use of the service and the time of the survey, such as graduation
from job-training or school, residential relocation and so on.
Because of the lack of a probability sample of services, the results cannot be generalized to the
entire JARC program. Detailed case studies of the 26 services yield insights into the types of
benefits that are being provided overall in these cases and the planning and programmatic
environment within which they operate
Perception of isolated chords: Examining frequency of occurrence, instrumental timbre, acoustic descriptors and musical training
This study investigated the perception of isolated chords using a combination of experimental manipulation and exploratory analysis. Twelve types of chord (five triads and seven tetrads) were presented in two instrumental timbres (piano and organ) to listeners who rated the chords for consonance, pleasantness, stability and relaxation. Listener ratings varied by chord, by timbre, and according to musical expertise, and revealed that musicians distinguished consonance from the other variables in a way that other listeners did not. To further explain the data, a principal component analysis and linear regression examined three potential predictors of the listener ratings. First, each chord’s frequency of occurrence was obtained by counting its appearances in selected works of music. Second, listeners rated their familiarity with the instrumental timbre in which the chord was played. Third, chords were described using a set of acoustic features derived using the Timbre Toolbox and MIR Toolbox. Results of the study indicated that listeners’ ratings of both consonance and stability were influenced by the degree of musical training and knowledge of tonal hierarchy. Listeners’ ratings of pleasantness and relaxation, on the other hand, depended more on the instrumental timbre and other acoustic descriptions of the chord
Lensing in the Blue II: Estimating the Sensitivity of Stratospheric Balloons to Weak Gravitational Lensing
The Superpressure Balloon-borne Imaging Telescope (SuperBIT) is a
diffraction-limited, wide-field, 0.5 m, near-infrared to near-ultraviolet
observatory designed to exploit the stratosphere's space-like conditions.
SuperBIT's 2023 science flight will deliver deep, blue imaging of galaxy
clusters for gravitational lensing analysis. In preparation, we have developed
a weak lensing measurement pipeline with modern algorithms for PSF
characterization, shape measurement, and shear calibration. We validate our
pipeline and forecast SuperBIT survey properties with simulated galaxy cluster
observations in SuperBIT's near-UV and blue bandpasses. We predict imaging
depth, galaxy number (source) density, and redshift distribution for
observations in SuperBIT's three bluest filters; the effect of lensing sample
selections is also considered. We find that in three hours of on-sky
integration, SuperBIT can attain a depth of b = 26 mag and a total source
density exceeding 40 galaxies per square arcminute. Even with the application
of lensing-analysis catalog selections, we find b-band source densities between
25 and 30 galaxies per square arcminute with a median redshift of z = 1.1. Our
analysis confirms SuperBIT's capability for weak gravitational lensing
measurements in the blue.Comment: Submitted to Astronomical Journa
Lensing in the Blue. II. Estimating the Sensitivity of Stratospheric Balloons to Weak Gravitational Lensing
The Superpressure Balloon-borne Imaging Telescope (SuperBIT) is a diffraction-limited, wide-field, 0.5 m, near-infrared to near-ultraviolet observatory designed to exploit the stratosphere's space-like conditions. SuperBIT's 2023 science flight will deliver deep, blue imaging of galaxy clusters for gravitational lensing analysis. In preparation, we have developed a weak-lensing measurement pipeline with modern algorithms for PSF characterization, shape measurement, and shear calibration. We validate our pipeline and forecast SuperBIT survey properties with simulated galaxy cluster observations in SuperBIT's near-UV and blue bandpasses. We predict imaging depth, galaxy number (source) density, and redshift distribution for observations in SuperBIT's three bluest filters; the effect of lensing sample selections is also considered. We find that, in three hours of on-sky integration, SuperBIT can attain a depth of b = 26 mag and a total source density exceeding 40 galaxies per square arcminute. Even with the application of lensing-analysis catalog selections, we find b-band source densities between 25 and 30 galaxies per square arcminute with a median redshift of z = 1.1. Our analysis confirms SuperBIT's capability for weak gravitational lensing measurements in the blue
The Timbre Perception Test (TPT): A new interactive musical assessment tool to measure timbre perception ability
To date, tests that measure individual differences in the ability to perceive musical timbre are scarce in the published literature.The lack of such tool limits research on how timbre, a primary attribute of sound, is perceived and processed among individuals.The current paper describes the development of the Timbre Perception Test (TPT), in which participants use a slider to reproduce heard auditory stimuli that vary along three important dimensions of timbre: envelope, spectral flux, and spectral centroid. With a sample of 95 participants, the TPT was calibrated and validated against measures of related abilities and examined for its reliability. The results indicate that a short-version (8 minutes) of the TPT has good explanatory support from a factor analysis model, acceptable internal reliability (α=.69,ωt = .70), good test–retest reliability (r= .79) and substantial correlations with self-reported general musical sophistication (ρ= .63) and pitch discrimination (ρ= .56), as well as somewhat lower correlations with duration discrimination (ρ= .27), and musical instrument discrimination abilities (ρ= .33). Overall, the TPT represents a robust tool to measure an individual’s timbre perception ability. Furthermore, the use of sliders to perform a reproductive task has shown to be an effective approach in threshold testing. The current version of the TPT is openly available for research purposes
H. N. Werkman
A piece commissioned for COLDFRONT – Singular Vispo :: First Encounters.
Artists were asked to talk about their introduction to Visual Poetry and the piece of work that changed the way they saw language
Mechanics of the exceptional anuran ear
The anuran ear is frequently used for studying fundamental properties of vertebrate auditory systems. This is due to its unique anatomical features, most prominently the lack of a basilar membrane and the presence of two dedicated acoustic end organs, the basilar papilla and the amphibian papilla. Our current anatomical and functional knowledge implies that three distinct regions can be identified within these two organs. The basilar papilla functions as a single auditory filter. The low-frequency portion of the amphibian papilla is an electrically tuned, tonotopically organized auditory end organ. The high-frequency portion of the amphibian papilla is mechanically tuned and tonotopically organized, and it emits spontaneous otoacoustic emissions. This high-frequency portion of the amphibian papilla shows a remarkable, functional resemblance to the mammalian cochlea
SuperBIT Superpressure Flight Instrument Overview and Performance: Near-diffraction-limited Astronomical Imaging from the Stratosphere
SuperBIT was a 0.5 m near-UV to near-infrared wide-field telescope that launched on a NASA superpressure balloon into the stratosphere from New Zealand for a 45-night flight. SuperBIT acquired multiband images of galaxy clusters to study the properties of dark matter using weak gravitational lensing. We provide an overview of the instrument and its various subsystems. We then present the instrument performance from the flight, including the telescope and image stabilization system, the optical system, the power system, and the thermal system. SuperBIT successfully met the instrument’s technical requirements, achieving a telescope pointing stability of 0.″34 ± 0.″10, a focal plane image stability of 0.″055 ± 0.″027, and a point-spread function FWHM of ∼0.″35 over 5-minute exposures throughout the 45-night flight. The telescope achieved a near-diffraction-limited point-spread function in all three science bands (u, b, and g). SuperBIT served as a pathfinder to the GigaBIT observatory, which will be a 1.34 m near-UV to near-infrared balloon-borne telescope
Perceived and functional independence in travel: assessing the role of neighborhood factors and community-based mobility services for persons with disabilities
We examine the relationships between environmental factors (neighborhood characteristics and community-based transportation services) and the degree of perceived and functional independence in travel for a sample of persons with disabilities residing in urban and suburban US locations with a wide variety of neighborhood conditions. Perceived ability is a self-reported measure on a Likert-type ordinal scale while the functional ability scale reflects the “Mode of Transportation” and “Shopping” aspects of the Lawton-Brody Instrument Activities of Daily Living scale. Neighborhood characteristics examined are walkability, population density, percent owner-occupied housing and age and racial/ethnic diversity, while community-based transportation services considered are volunteer driver services, van-based demand response programs and taxi services that are operated either by community organizations, senior care centers or transit agencies. Using cluster analysis, we first cluster persons with disabilities into three homogeneous groups based on their sociodemographic, health and disability status. Results from ordered probit models that start with an assessment of endogeneity between the independence scales and the environmental factors and controls for cluster membership, indicate that neighborhood characteristics and community-based transportation services interact in complex ways and that while neighborhood characteristics are important, they become less important in explaining perceived and functional independence when some of the community transportation factors are introduced. The results imply that communities may support persons with disabilities by pursuing planning and programmatic activities that enhance both aspects of environmental factors - neighborhood characteristics that support an independent and active life as well as specialized community-based transportation services