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This study focuses on a novel, multipass, acoustically open photoacoustic detector designed for fast-response high-sensitivity detection of formaldehyde adsorption by bamboo charcoal in an ambient atmosphere. The detection range, estimated from formaldehyde measurements at a wavenumber of around 2805 cm −1 , is 0-2.0 parts per million by volume. In this work, photoacoustic (PA) detection with various bamboo charcoals was analyzed at our laboratory for the detection of a photoacoustic signal using a pulsed laser system and the comparative performances of the charcoals were studied. The PA system is applicable to pollution monitoring and detection of hazardous gases in an indoor environment.

This research assessed the feasibility of using a neural network to detect low levels of damage in small samples of medium density fiberboard (MDF). The neural network was a three-layer back-propagation network. The undamaged stress wave frequency spectrum patterns were trained by the neural network. The trained patterns were then compared to stress waves patterns taken from MDF samples loaded to various percentages of their estimated failure load. In this experiment, if an application load is below the proportional limit, a small change in wave patterns occurs. The neural network has the unique ability to train data to recognize spectral patterns and has been used with success for the detection of structural damage.

The aim of this research is to develop and validate an experimental model testing method in the erhu instrument. The model analysis is dependent on the dynamic behavior of materials which results the relationships to be naturally excited due to the structure. There are three major factors which would directly affect the performance of erhu vibroacoustic: (1) string, (2) vibrating skin, and (3) wooden soundbox. However, the transducer mass effect is the significant impact factor in the membrane vibration measurement. The attention is focused on the erhu skin vibration modes by using the scanning laser method. The method for experimental mode shapes of erhu skin was notable in that the equipment assembled a loudspeaker, a signal point laser, and a scanning laser vibrometer. The mode shapes can be excited depending on the white noise with plane acoustic wave to push on the skin surface. The scanning laser method is content two types of laser doppler vibrometer for various purpose. The single point laser measured the driving point vibration as the reference in the center of the skin surface. The responses were measured by the scanning laser vibrometer with 276 measuring points on the surface. The results showed the vibroacoustic of erhu skin which the various mode shapes are dependent on the frequency diversifications. The mode shapes of the erhu skin can be characteristic into five vibroacoustic patterns by the various frequency ranges (20 to 5,000 Hz).  Obviously, the scanning laser method is a convenient and readily reproducible setup to evaluate in the erhu vibroacoustic properties. As an engineering application, the proposed method can be served as a fundamental tool when predicting or even suppressing the possible excitations associated with particular vibration modes in the mechanical designs of the instruments.

To keep the next generation safe from the energy depletion crisis and slow the impact of climate change. The world is accelerating the energy transition with the goal of net zero emissions. National Pingtung University of Science and Technology / NPUST established a Sustainable Circular Economy R&D Center / SCERDC. To develop innovative technologies and combine green energy applications across fields for the waste materials, waste recycling and energy saving and carbon reduction of agriculture, forestry, fishery and animal husbandry. Add more strength to “circular economy” and “sustainable environment”.