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102/10/29 14:00 台灣大學工程科學及海洋工程學系黃心豪助理教授演講
演講公告
張貼人：網站管理員 ╱ 公告日期：2013-10-23演 講 公 告
主講人：黃心豪 助理教授
地點：中央大學科學一館S-325教室
摘要：
講題：Recent Development in Design of Engineering Materials and Structures
主講人：黃心豪 助理教授
台灣大學工程科學及海洋工程學系
時間：10月29日（星期二）下午2點
地點：中央大學科學一館S-325教室
摘要：
In the first part, specifically designed man-made engineering materials will be introduced. They are so called “Acoustic metamaterials”. Acoustic metamaterials are media possessing exceptional elastic material properties not commonly found in natural materials. These material properties are enacted, not due to chemical composition, but by structurally designed man-made microstructures. For instance, an acoustic metamaterial exhibits negative effective mass density when the material consists of internal resonant microstructural units. It is found that the effective mass density becomes frequency dependent and displays negativity for frequencies near the resonant frequency of the internal resonators. Negative material property creates stop bands so that the stress wave propagation is prohibited. The effect leads to structural applications like vibration control, impact protection and shock wave mitigation. By incorporating the mass-in-mass type as well as the lateral resonant type microstructures, the metamaterial is capable of exhibiting effective negative mass density, or effective negative elastic modulus, or both. Harmonic wave propagation in such medium is studied based on an effective continuum model. Interesting transient wave motion, in addition, is presented through numerical simulations based on simplified discrete element model. The dynamic characteristics and applications of unusual wave motion are investigated and discussed. In the second part, the speaker will present the recent work regarding engineering structures based on the concept of structural designs.
最後修改時間：2013-10-30 PM 2:22
