The prediction of traffic noise using a scale model

The installation of sound-absorptive materials near the edge of a noise barrier is known to increase its insertion loss. First, scale-model experiments were performed to compare the performance of barriers that have absorptive edge linings with that of linearly extended, rigid uniform barriers and T-shaped barriers. The issue of effective positioning of the sound-absorptive material was also addressed. It was found that in terms of material use, an absorptive treatment was the most effective treatment for reducing the sound level in the shadow zone for a given barrier height. It was concluded that absorptive edge treatments may offer the opportunity to design effective treatments that could be retrofitted to existing barrier installations to improve their effectiveness. Preliminary field measurements were performed near South Bend, Indiana. The performance of an existing barrier was evaluated. Predictions of its performance made using the FHWA Traffic Noise Model were verified. An acoustical treatment was added to one vertical edge of the highway noise barrier. The results for the performance of the acoustical treatment measured in the field confirmed the trends of the scale-model laboratory measurements.

Download Full-text

Sound source for scale model measurements of traffic noise

Applied Acoustics ◽

10.1016/0003-682x(88)90071-0 ◽

1988 ◽

Vol 24 (1) ◽

pp. 63-70 ◽

Cited By ~ 1

Author(s):

Josef Novák

Keyword(s):

Sound Source ◽

Traffic Noise ◽

Scale Model

Download Full-text

Evaluation of road traffic noise abatement by vegetation treatment in a 1:10 urban scale model

The Journal of the Acoustical Society of America ◽

10.1121/1.4937769 ◽

2015 ◽

Vol 138 (6) ◽

pp. 3884-3895 ◽

Cited By ~ 21

Author(s):

Hyung Suk Jang ◽

Sung Chan Lee ◽

Jin Yong Jeon ◽

Jian Kang

Keyword(s):

Road Traffic ◽

Traffic Noise ◽

Scale Model ◽

Road Traffic Noise ◽

Noise Abatement

Download Full-text

The Performance of a Low Berm in Reducing Traffic Noise

INTER-NOISE and NOISE-CON Congress and Conference Proceedings ◽

10.3397/in-2021-1783 ◽

2021 ◽

Vol 263 (5) ◽

pp. 1227-1238

Author(s):

Paul Donavan ◽

Carrie Janello

Keyword(s):

Open Field ◽

Traffic Noise ◽

Diffraction Theory ◽

Noise Model ◽

Scale Model ◽

Edge Diffraction ◽

Double Edge ◽

Noise Measurements ◽

The Difference ◽

A Site

Traffic noise measurements were made behind a low, earth berm and in an adjacent open field to estimate insertion loss. The traffic was comprised of a mix of light vehicles, heavy trucks, and some medium trucks. The berm had a height of 1.65 meters above the roadway and began at the outside shoulder of a four-lane highway along U.S. Highway 101 in Northern California. Two microphone positions were located on the far side of the berm at distances of 28 and 40 meters from the center of the near lane of vehicular traffic. Away from the berm, a microphone was placed in an open field at 28 meters from the highway at a site upstream of the berm. The difference between the open location and those behind the berm were 11.6 and 9.9 dB for the 28- and 40-meter locations, respectively. The reductions obtained with the berm are compared to double edge diffraction theory and acoustic scale model results from the literature. The results of this study are reviewed in this paper and a comparison to FHWA Traffic Noise Model results is presented.

Download Full-text

Modeling Within-Person Variance in Reaction Time Data of Older Adults

GeroPsych ◽

10.1024/1662-9647/a000045 ◽

2011 ◽

Vol 24 (4) ◽

pp. 169-176 ◽

Cited By ~ 4

Author(s):

Philippe Rast ◽

Daniel Zimprich

Keyword(s):

Reaction Time ◽

Cognitive Aging ◽

Reaction Times ◽

Reaction Time Task ◽

Reaction Time Data ◽

Scale Model ◽

Time Data ◽

Time Task ◽

The Mean ◽

Second Wave

In order to model within-person (WP) variance in a reaction time task, we applied a mixed location scale model using 335 participants from the second wave of the Zurich Longitudinal Study on Cognitive Aging. The age of the respondents and the performance in another reaction time task were used to explain individual differences in the WP variance. To account for larger variances due to slower reaction times, we also used the average of the predicted individual reaction time (RT) as a predictor for the WP variability. Here, the WP variability was a function of the mean. At the same time, older participants were more variable and those with better performance in another RT task were more consistent in their responses.

Download Full-text

Using the Rating Scale Model to Examine the Psychometric Properties of the Self-Efficacy Scale for Driver Competence

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000063 ◽

2011 ◽

Vol 27 (3) ◽

pp. 164-170 ◽

Cited By ~ 1

Author(s):

Anna Sundström

Keyword(s):

Psychometric Properties ◽

Self Efficacy ◽

Rating Scale ◽

Measurement Precision ◽

The Self ◽

Test Theory ◽

Self Report ◽

Scale Model ◽

Validity And Reliability ◽

Two Samples

This study evaluated the psychometric properties of a self-report scale for assessing perceived driver competence, labeled the Self-Efficacy Scale for Driver Competence (SSDC), using item response theory analyses. Two samples of Swedish driving-license examinees (n = 795; n = 714) completed two versions of the SSDC that were parallel in content. Prior work, using classical test theory analyses, has provided support for the validity and reliability of scores from the SSDC. This study investigated the measurement precision, item hierarchy, and differential functioning for males and females of the items in the SSDC as well as how the rating scale functions. The results confirmed the previous findings; that the SSDC demonstrates sound psychometric properties. In addition, the findings showed that measurement precision could be increased by adding items that tap higher self-efficacy levels. Moreover, the rating scale can be improved by reducing the number of categories or by providing each category with a label.

Download Full-text

An IRT Investigation of the Validity of Non-Patient Analogue Research Using the Beck Depression Inventory

European Journal of Psychological Assessment ◽

10.1027/1015-5759.11.1.14 ◽

1995 ◽

Vol 11 (1) ◽

pp. 14-20 ◽

Cited By ~ 22

Author(s):

Sean M. Hammond

Keyword(s):

Differential Item Functioning ◽

Beck Depression Inventory ◽

Rating Scale ◽

Latent Trait ◽

Scale Model ◽

Item Functioning ◽

Two Samples ◽

Patient Groups ◽

Analogue Research ◽

Rating Scale Model

This paper presents an IRT analysis of the Beck Depression Inventory which was carried out to assess the assumption of an underlying latent trait common to non-clinical and patient samples. A one parameter rating scale model was fitted to data drawn from a patient and non-patient sample. Findings suggest that while the BDI fits the model reasonably well for the two samples separately there is sufficient differential item functioning to raise serious duobts of the viability of using it analogously with patient and non-patient groups.

Download Full-text