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 $10,000 and two-thirds of the respondents earning$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 $10,000 and two-thirds of the respondents earning$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

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

Implementation of transaction and concurrency control support in a temporal DBMS

Transactions and concurrency control are significant features in database systems, facilitating functions both at user and system level. However, the support of these features in a temporal DBMS has not yet received adequate research attention. In this paper, we describe the techniques developed in order to support transaction and concurrency control in a temporal DBMS that was implemented as an additional layer to a commercial DBMS. The proposed techniques make direct use of the transaction mechanisms of the DBMS. In addition, they overcome a number of limitations such as automatic commit points, lock release and log size increment, which are imposed by the underlying DBMS. Our measurements have shown that the overhead introduced by these techniques is negligible, less than 1% in all cases. The approach undertaken is of general interest, it can also be applied to non-temporal DBMS extensions. Copyright (C) 1998 Elsevier Science Ltd. All rights reserved

Analysis of Employment Transportation Services for the JobLinks Program

Affordable and reliable transportation to work is a critical requirement for successful employment outcomes of low-wage workers. Employment Transportation services are specially funded services to transport low-income individuals to employment locations and other destinations that support work, such as job-training centers and childcare facilities. ET services have been funded by a variety of sources including the Job Access and Reverse Commute (JARC) program administered by the Federal Transit Administration (FTA) of the U.S. Department of Transportation, with match from other sources. ET services in a region are developed by means of Coordinated Human Services Transportation Plan (CHSTP), a planning mechanism to identify the transportation needs of mobility-disadvantaged individuals, including low-wage workers, seniors, persons with disabilities, and other disadvantaged groups, in coordination with public, private and non-profit organizations involved in their well-being. The objective of this report is to examine the role of workforce development agencies in the CHSTP process and to present findings regarding the labor market and mobility outcomes of low-wage workers who use ET services to access jobs and job training sites. The analysis is based on primary data collected from surveys of lead organizations responsible for developing the CHSTP and partner organizations (including workforce development agencies), in 24 urban, small urban and rural areas located in 10 federal regions. Representatives of these organizations provided insights regarding their activities relating to plan and project development. Program managers and users of a total of 26 transit-based ET services operating in these areas were also surveyed, providing insights into the nature of service operations and labor market and transportation outcomes experienced

Case studies of the new freedom program

The New Freedom (NF) transportation program was established by the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU, 2005), as a formula program to provide funding for transportation projects designed to reduce mobility barriers experienced by persons with disabilities. Regulations stipulate that NF-funded transportation projects be developed through Coordinated Human Services Transportation Plans (CHSTP), that are developed jointly by organizations in transportation, human and social services, workforce development, labor and economic development, private employers, faith-based organizations and other organizations involved in the well-being of persons with disabilities, seniors and low-wage workers. This report provides an exploratory overview of mobility and perceptual outcomes experienced by users of transportation-based NF programs, based on survey-based information

Empirical evaluation of energy saving margins in backbone networks

Fueled by concern over the energy consumption of backbone networks, lot's of work has recently gone into proposals for energy-aware traffic engineering and routing. Local and network-wide policies have been developed for switching off network interfaces and concentrating traffic in as few links as allowed by SLA constraints. In this work we examine empirically the energy saving margins of such policies using extensive data from a national and a pan-European research and academic network. We analyze the dependence of such margins on several parameters, including the level of energy proportionality, QoS constraints and the geographic span of a network. Our findings reveal that with existing devices, smart powering-off can save more than 50% of currently consumed energy, and that energy-aware traffic engineering has still quite away to go before it can be made redundant by improvements in the energy proportionality of devices

Advanced hardware-in-the-loop testing chain for investigating interactions between smart grid components during transients

Aiming to investigate the possible interactions between smart grid components during transient events, an advanced hardware-in-the-loop testing chain for the validation of novel smart grid solutions is proposed in this paper. The testing chain is directed towards both academic and industrial hardware-in-the-loop users, e.g., relay manufacturers, power electronics manufacturers and DSOs/TSOs. All different hardware-in-the-loop simulation setups, ranging from simple local simulations up to more elaborate, power hardware-in-the-loop simulations, are discussed, forming a solid testing chain. The interactions during transients, which can be investigated at each step, are analytically derived to emphasize the insights that each step can offer to the performed component validation. To highlight the applicability of the proposed hardware-in-the-loop testing chain, when validating smart grid components, a case study concerning the testing of a microgrid transition algorithm, between the interconnected and islanded modes of operation, is considered for a real microgrid. Particularly, the interactions between an advanced grid-forming inverter and the already existing grid-following inverters of the microgrid are investigated during normal and abnormal grid conditions, while following the appropriate steps of the proposed testing chain