演講公告
新聞標題: ( 2012-10-15 )
演講主題:2012 NCTS/CMMSC Seminar on PDEs, Theory and Applications
主講人:陳健章 博士 (丘成桐中心)
演講日期:2012年10月23日(星期二) 下午 3:30 –4:20
演講地點:(光復校區) 科學一館 307室
摘要內容:
Sound source localization is a physiological ability of animals to process
sensory information regarding the orientation and magnitude of sound pressure stimulation. The source localization is achieved via the differences of sound intensity and arrival time sensed by two ears which are geometrically close but far away from the sound sources.
For a large mammal, two auditory organs are acoustically isolated by its head to have a large interaural distance (ID). For instance, the auditory system of an adult human with an ID of 20 cm can have an interaural time delay (ITD) of 600 μs and interaural intensity difference (IID) of about 16 dB between the ears with a 5 KHz tone sound pressure stimulation. Such minute ITD and IID are adequate for reliable time coding and processing in auditory nervous systems* *for sound source detection. In contrast, two auditory organs of small animals are quite
close to each other, so there would be a problem for the auditory system to experience insignificant interaural differences resulted by the tiny ID, about two orders of magnitude smaller than that of large animals.
Therefore, the methodology of sound source localization in the tiny auditory system could lead the way to develop the next generation acoustic sensing and tracking microsystems like hearing aids, robots,
and bionic military devices. In this talk, an acoustical structure with a central floating supported sensing diaphragm in microscale will be introduced for sound source localization by hybridizing the auditory mechanically coupled principle of the parasitoid fly (*Ormia ochracea*) and the clover stem. Meanwhile, a corresponding physical response model with air damping effects for the auditory dynamical behaviors of the biomometic diaphragm will be fully elucidated. In final, the non-ideal effect occurred in hearing aids and the application of acoustic-energy harvesting will also then be briefly introduced.
