| Author: | Zhang, Yanling |
| Title: | A mathematical approach to acoustic comfort in classrooms |
| Advisors: | Mak, Cheukming (BSE) |
| Degree: | M.Eng. |
| Year: | 2019 |
| Subject: | Hong Kong Polytechnic University -- Dissertations School buildings -- Acoustics Classrooms Architectural acoustics |
| Department: | Department of Building Services Engineering |
| Pages: | x, 80 pages : color illustrations |
| Language: | English |
| Abstract: | The classrooms in universities are the main places for students' learning. Students spend about 9 hours in the classroom every day. The acoustic comfort in the classroom affects students' health and learning efficiency. Therefore, this dissertation studied the acoustic indicators that affect the sound comfort of classrooms and develops the acoustic comfort index model in the classroom. This model can be as an evaluation indicator or to optimize the indoor acoustic environment during the design phase. Which might have a significant impact on the health and productivity of teachers and students in the classroom. This experiment mainly measures the noise level, clarity and other indicators that affect the sound comfort in the classroom. At the same time, the students are surveyed to evaluate the comfort under various acoustic indicators and obtain the weights of various acoustic comfort factors. Using the analytic hierarchy process and fuzzy comprehensive evaluation method can obtain actual classroom comfort. The acoustic comfort index model in the classroom was acquired by using correlation analysis and regression fitting. Under the indicators of the classroom parameters of the Hong Kong Polytechnic University, Mathematical analysis of 238 questionnaires and 8 classrooms with different scales and measuring the sound field in the classroom were obtained reliable data to summarize complex indicators and established multiple linear models. The parameters of sound transmission index (STI), signal to noise ratio (SNR), clarity, reverberation time (T30) were assessed the classroom acoustic comfort properly. The analysis showed the correlation between signal-to-noise ratio and speech transmission index. The Pearson number of 0.983 shows that SNR is closely related to STI. Although many studies have pointed out that noise is conducive to sound comfort at a lower level (<30dB). Regression analysis of single-valued acoustic parameters and acoustic comfort in the classroom showed that the noise level is generally higher than 50dB in the classrooms of the Hong Kong Polytechnic University. The greater the noise level of the noise measured in the experiment, the smaller the comfort of the classroom and the linear correlation. Design parameters such as reverberation time and clarity in the classroom are positively correlated with classroom acoustic comfort. According to multiple linear regression analysis, the beta value of the noise signal (SNR) and related parameters in the classroom is significantly greater than the classroom design parameters, so the effect of noise on the linear regression coefficient is more significant. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 991022370953303411.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 1.57 MB | Adobe PDF | View/Open |
Copyright Undertaking
As a bona fide Library user, I declare that:
- I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
- I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
- I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.
By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.
Please use this identifier to cite or link to this item:
https://theses.lib.polyu.edu.hk/handle/200/10394