scholarly journals Acoustic quality of critical habitats for three threatened whale populations

2013 ◽  
Vol 17 (2) ◽  
pp. 174-185 ◽  
Author(s):  
R. Williams ◽  
C. W. Clark ◽  
D. Ponirakis ◽  
E. Ashe
Keyword(s):  
Acoustic Quality

scholarly journals Environmental Acoustic Comfort in the Built Environment

2021 ◽  
Vol 9 (71) ◽  
Author(s):  
Margret Sibylle Engel ◽  
Júlio Otávio Herrmann ◽  
Paulo Henrique Trombetta Zannin
Keyword(s):  
Teaching And Learning ◽  
Physical Structure ◽  
Sharp Drop ◽  
Speech Transmission ◽  
Acoustic Quality ◽  
Teachers And Students ◽  
Acoustic Comfort ◽  
The 1960S ◽  
Acoustic Conditions

  The acoustic quality of classrooms has a strong influence on the teaching and learning process. This interference assessed using the impulsive technique to measure the rate of speech transmission (STI), reverberation time (RT) and sound definition (D50). These are the most relevant acoustic descriptors in the assessment of classrooms, where verbal exposure is the means of communication between teachers and students. The evaluation took place in two buildings of the Federal University of Paraná (UFPR), built in the 1960s and another in 2016. The measured values ​​of STI, provided in the classrooms' actual acoustic conditions, were used as an adjustment parameter for simulations made with the software ODEON. After carrying out the measurements and simulations, the dimensioning of improvements was possible. The acoustic simulations presented suggestions to qualify the quality of the classrooms' acoustic comfort, ensuring that teaching and learning to do not suffer losses due to the physical structure of the classrooms. The measured values ​​of STI, RT and D50 show that, in the old building, except for a single classroom that preserves the original ceiling that had a high sound absorption coefficient, it has reasonable values, below the ideal for classrooms, according to the IEC 60268-16 (2011) standard. The investigation showed that the rooms with a roof replaced by a PVC covering had a sharp drop in acoustic quality. The newest building has classrooms with proper acoustic comfort conditions.

scholarly journals Classroom acoustics: Listening problems in children

2019 ◽  
Vol 27 (1) ◽  
pp. 47-59 ◽  
Author(s):  
Flavia Gheller ◽  
Elisa Lovo ◽  
Athena Arsie ◽  
Roberto Bovo
Keyword(s):  
Auditory Processing ◽  
Signal To Noise Ratio ◽  
Cognitive Effort ◽  
Listening Skills ◽  
Noisy Environments ◽  
Acoustic Characteristics ◽  
Classroom Acoustics ◽  
Acoustic Quality ◽  
The Impact

The acoustic quality of classrooms is crucial for children’s listening skills and consequently for their learning. Listening abilities in kids are still developing, and an environment with inadequate acoustic characteristics may create additional problems in speech perception and phonetic recognition. Background noise or reverberation may cause auditory processing problems and greater cognitive effort. There are also other elements which can make difficulty in listening and understanding in noisy environments an even more serious problem, such as learning disabilities, mild to severe hearing loss or bilingualism. Therefore, it is important to improve the acoustic quality of the classrooms, taking into account the specific needs of children in terms of signal-to-noise ratio and reverberation time, in order to ensure a proper quality of listening. The aim of this work is to analyse, through the review of previous studies, the impact that the acoustic of classrooms has on children’s listening skills and learning activities.

on the relationship between acoustic quality of concert halls and the architectural style

2015 ◽  
Author(s):  
Jules Ghislain Slama ◽  
Patricia Figueira Lassance ◽  
Deborah Luiza Canabarro Rangel ◽  
Pedro Augusto Ferreira Rodrigues
Keyword(s):  
Architectural Style ◽  
Acoustic Quality ◽  
Concert Halls ◽  
The Relationship

Calculation Models for Acoustic Analysis of St. Elizabeth of Hungary Church in Jaworzno Szczakowa

2016 ◽  
Vol 41 (3) ◽  
pp. 485-498 ◽  
Author(s):  
Krzysztof Kosała
Keyword(s):  
Acoustic Analysis ◽  
Roman Catholic ◽  
Acoustic Properties ◽  
Roman Catholic Church ◽  
Global Index ◽  
Index Method ◽  
Acoustic Quality ◽  
Single Number ◽  
Calculation Models

Abstract In parallel with research conducted using conventional methods, a uniform index method for assessing the acoustic quality of Roman Catholic churches has been developed. The latest version of the index method has been created using the index observation matrix of 12 churches which have been rated by means of the single number global index. Assessments of the acoustic quality of any Roman Catholic church, using two calculation models: the Global Acoustic Properties Index (GAP) and the Global Index (GI), are shown in the article. The verification was performed on the example of one church, showing the way of calculating global indices to assess the acoustic quality of a new facility. The next stages in the development of the index method for assessing the acoustic quality of churches were taking into account the audience, using simulation tests and determining the spatial distribution of the single number GAP index in an examined church. An attempt to use the GAP and GI calculation models to assess the acoustic properties of some churches is also shown in the article.

An Experimental Study to Find the Acoustic Quality Indicators of Mulberry Wood

2010 ◽  
Author(s):  
Hossein Mansour ◽  
Mehdi Behzad
Keyword(s):  
Wood Species ◽  
Musical Instrument ◽  
Musical Instruments ◽  
Raw Material ◽  
Test Case ◽  
High Quality ◽  
Perceptual Knowledge ◽  
Acoustical Properties ◽  
Acoustic Quality

Morus Alba or mulberry is a wood species that is broadly used in making musical instruments in Eastern countries. However, the mechanical and acoustical properties of this type of wood are not investigated properly. In this study a set of features, previously examined for other species, are applied to this wood and its acoustic quality is evaluated. Setar, a Persian musical instrument made of mulberry wood, is selected as the test case of this experiment. Different samples of wood are gathered and categorized based on their appropriateness for Setar construction. The quality of each sample is identified based on the Perceptual knowledge of professional Setar makers. The most effective features are then selected and their average values are calculated for high quality samples. The result of this study helps Setar makers to select proper raw material before making an instrument. In addition, this approach can be applied to other wood species used in music industry.

scholarly journals Relationships between Subjective and Objective Acoustical Measures in Churches

1997 ◽  
Vol 4 (1) ◽  
pp. 1-20 ◽  
Author(s):  
António P.O. Carvalho ◽  
António E.J. Morgado ◽  
Luís Henrique
Keyword(s):  
Correlation Coefficients ◽  
Field Measurements ◽  
Room Acoustics ◽  
Significant Relationships ◽  
Architectural Features ◽  
Live Music ◽  
Acoustic Quality ◽  
Catholic Churches ◽  
Made In

This study reports on subjective and objective acoustical field measurements made in a survey of 36 Catholic churches in Portugal built in the last 14 centuries. Monaural acoustical measurements (RT, EDT. C80, D50, TS and L) were taken at several source/receiver locations in each church and a group of college students was asked to judge the subjective quality of music. The listeners in each church evaluated live music performances at similar locations in each room. Evaluation sheets were used to record the listeners' overall impressions of room acoustic quality and also Loudness, Reverberance. Intimacy. Envelopment. Directionality, Balance, Clarity, Echoes and Background Noise. This paper concentrates on the relationships of the subjective parameters with the objective room acoustics measures and with the architectural features of the churches. Correlation analyses and statistical modeling identified significant relationships among the measures. For instance, linear correlation coefficients (| R|) of 0.8–0.9 were found for the relationships: Reverberance/RT and Clarity/C80; the maximum | R| found was 0.93 for Echoes/RT. Regarding architectural features the maximum | R | found was 0.87 between Intimacy and Total Volume.

scholarly journals Penilaian Kualitas Akustik Masjid Raudhaturrahman Padang Tiji Menggunakan Simulasi Ecotect

2020 ◽  
Vol 2 (2) ◽  
pp. 357-367
Author(s):  
Yulida Yani
Keyword(s):  
Background Noise ◽  
Simulation Method ◽  
Reverberation Time ◽  
Religious Rituals ◽  
Religious Significance ◽  
Acoustic Quality ◽  
Unique Shape ◽  
High Degree

Mosque is a place of worship for Moslems. It has profound religious significance for the community; it is important that people feel serenity therein. In addition, they need to be able to hear sounds clearly so that they can perform their religious rituals like prayers smoothly and it is also crucial for them to hear speeches with a high degree of intelligibility. This study assessed the acoustic quality of Raudhaturrahman prayer's room, having a unique shape with the dome ceiling covering all dimensions of the building.  This study aims at finding the condition, causes, and improving the acoustic quality to meet the prayer's room acoustic needs.  This study specifically focused on calculating the background noise and reverberation time using the Ecotect Simulation method.  The simulation result demonstrates that the calculation of reverberation time (RT) and the measurement of background noise have not met the desired standard. This study found that the value for RT with occupancy 0%, 50%, 100% is 18, 29s, 7, the 80s, and 4, 71s.  In addition, the result of the background noise is 60 dB.  In conclusion, the acoustic of the Raudhaturrahmah mosque prayer's room is of inferior quality since it does not meet the standard of reverberation time (RT) and background noise for the speech purpose of the room.

scholarly journals The Effects of L1 English Constraints on the Acquisition of the L2 Spanish Alveopalatal Nasal

2021 ◽  
Vol 12 ◽  
Author(s):  
Sara Stefanich ◽  
Jennifer Cabrelli
Keyword(s):  
English Learners ◽  
English Speakers ◽  
Perceptual Cues ◽  
L2 Acquisition ◽  
Advanced Learners ◽  
Acoustic Quality ◽  
Potential Difficulty ◽  
L2 Spanish ◽  
L1 English

This study examines whether L1 English/L2 Spanish learners at different proficiency levels acquire a novel L2 phoneme, the Spanish palatal nasal /ɲ/. While alveolar /n/ is part of the Spanish and English inventories, /ɲ/, which consists of a tautosyllabic palatal nasal+glide element, is not. This crosslinguistic disparity presents potential difficulty for L1 English speakers due to L1 segmental and phonotactic constraints; the closest English approximation is the heterosyllabic sequence /nj/ (e.g., “canyon” /kænjn/ ['khæn.jn], cf. Spanish cañón “canyon” /kaɲon/ [ka.'ɲon]). With these crosslinguistic differences in mind, we ask: (1a) Do L1 English learners of L2 Spanish produce acoustically distinct Spanish /n/ and /ɲ/ and (1b) Does the distinction of /n/ and /ɲ/ vary by proficiency? In the case that learners distinguish /n/ and /ɲ/, the second question investigates the acoustic quality of /ɲ/ to determine (2a) if learners' L2 representation patterns with that of an L1 Spanish representation or if learners rely on an L1 representation (here, English /nj/) and (2b) if the acoustic quality of L2 Spanish /ɲ/ varies as a function of proficiency. Beginner (n = 9) and advanced (n = 8) L1 English/L2 Spanish speakers and a comparison group of 10 L1 Spanish/L2 English speakers completed delayed repetition tasks in which disyllabic nonce words were produced in a carrier phrase. English critical items contained an intervocalic heterosyllabic /nj/ sequence (e.g., ['phan.jə]); Spanish critical items consisted of items with either intervocalic onset /ɲ/ (e.g., ['xa.ɲa]) or /n/ ['xa.na]. We measured duration and formant contours of the following vocalic portion as acoustic indices of the /n/~/ɲ/ and /ɲ/ ~/nj/ distinctions. Results show that, while L2 Spanish learners produce an acoustically distinct /n/ ~ /ɲ/ contrast even at a low level of proficiency, the beginners produce an intermediate /ɲ/ that falls acoustically between their English /nj/ and the L1 Spanish /ɲ/ while the advanced learners' Spanish /ɲ/ and English /nj/ appear to be in the process of equivalence classification. We discuss these outcomes as they relate to the robustness of L1 phonological constraints in late L2 acquisition coupled with the role of perceptual cues, functional load, and questions of intelligibility.

Diagnosis of the Noise Discipline in Petrobras Offshore Units Projects

2004 ◽  
Author(s):  
Ernani L. Sztajnbok ◽  
Luiz Antonio Vaz Pinto ◽  
Arcanjo Lenzi ◽  
Fernando Pedrosa Guedes ◽  
Regina Ce´lia Vieira de Assis
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Boundary Element Method ◽  
Complex Problem ◽  
Noise Prediction ◽  
Offshore Platforms ◽  
Noise Sources ◽  
Acoustic Quality ◽  
Element Method

Health, comfort and the job efficiency of the crew of offshore platforms are factors deeply related to the acoustic quality of the places. The acoustic project of platforms include the noise prediction. It is a complex problem, because it involves several noise sources and receptors. Numeric methods such as Boundary Element Method and Finite Element Method are not still fully satisfactory for use in complex acoustic problems. This way, semi-empiric formulas and statistics methods are used in the prediction calculations. This paper describes some aspects of the Petrobras experience, along the years, in the performance of acoustic projects in offshore platforms. Finally, in this work, some important decisions are discussed for improvement of the acoustic quality of those operational units.

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