A study on supplying system of urgent warning signal into perfect insulated space

Research Project

Project/Area Number	02650419
Research Category	Grant-in-Aid for General Scientific Research (C)
Allocation Type	Single-year Grants
Research Field	建築環境・環境工学
Research Institution	Kyushu Institute of Design
Principal Investigator	FUJIWARA Kyoji Kyushu Institute of Design, Faculty of Design, Professor, 芸術工学部, 教授 (00038978)
Project Period (FY)	1990 – 1991
Project Status	Completed (Fiscal Year 1991)
Budget Amount *help	¥2,200,000 (Direct Cost: ¥2,200,000) Fiscal Year 1991: ¥300,000 (Direct Cost: ¥300,000) Fiscal Year 1990: ¥1,900,000 (Direct Cost: ¥1,900,000)
Keywords	Insulated Space / Urgent Warning Signals / Power Density Spectrum / Correlation Coefficient / Residual Energy Ratio / 完全遮音空間 / 電力スペクトル推定
Research Abstract	The purpose of this study was to develop a supplying system of the important signals for us into the insulated space. In this study as important and urgent warning signals such as ambulance, patrol car and fire truck were employed. If the warning signal is included in the incoming sound, only the warning signal was introduced into the insulated space. At the last stage this supplying system was installed on the personal computer. In this study the most important point is how to judge the urgent warning., signal. Both values of the auto correlation coefficient (CC) and the residual energy ratio (RER) of the power density spectrum (PDS) were used for the judgment, and those of incoming sound were compared with those of the reference sound. If the both of CC and RER satisfy the preset values, reference sound and incoming sound are considered to be the same signal. When the incoming sound is similar to the reference sound, the CC of the PDS is large and the RER is small. In this case it was very easy to judge the incoming sound. As a conclusion, it was confirmed that if the preset values 0.7 for CC and 0.2 for RER are given, and both values are used for the judgment, then certain warning signal can be extracted from the incoming sound.