Browsing by Author "Lin, Yu-Chih"

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Application of physical vapor deposition process to modify activated carbon fibers for ozone reduction
(2008-05-01)
Lin, Yu-Chih
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Chang, Chung-Liang
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Lin, Tser-Sheng
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Bai, Hsunling
;
Yan, Ming-Gu
This study utilized the activated carbon fiber (ACF) modified with metal catalyst via physical vapor deposition (PVD) process (ACF/PVD) to diminish ozone. Furthermore, the ozone removal efficiency of ACF/PVD was compared with that of original ACF and ACF modified with metal catalyst via impregnation process (ACF/impregnation). In addition to the kinds of coated metal and the inlet ozone concentrations, the effects of the coating thickness and the reaction temperature on ACF/PVD for ozone removal were also examined. The results indicate that the ozone removal efficiency of ACF/PVD is better than that of original ACF and ACF/impregnation. The ozone removal efficiency of different metal-coated ACF/PVD in the superior order is gold (Au), and manganese (Mn). The increase of Au-coated thickness (3 nm to 80 nm) on ACF/PVD will enhance the ozone removal. However, when the Mn-coated thickness on ACF/PVD is larger than 15 rim, the ozone removal efficiency displays a declining trend. Furthermore, a higher reaction temperature will result in a better ozone removal of ACF/PVD and the original ACF.
Applying spray pyrolysis to synthesize MnO (x) for decomposing isopropyl alcohol in ozone- and thermal-catalytic oxidation
(2009-07-01)
Chang, Chung-Liang
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Lin, Yu-Chih
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Bai, Hsunling
;
Liu, Yu-Huei
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環境工程研究所
Manganese oxides (MnO (x) ) were prepared by spray pyrolysis methods (Mn (S) ) and calcination at 600 and 1,000 A degrees C (Mn(600) and Mn(1000)) in this study. Further, the efficiencies of oxidizing isopropanol (IPA) by these MnO (x) utilizing ozone (OZCO) and thermal catalytic oxidation (TCO) were compared. The results indicated that Mn (S) , which are characterized by larger surface areas, processed gas hourly space velocity of 42,000 h(-1) and inlet IPA concentration of 400 ppm performing IPA decomposition efficiencies approaching 100%, and the reaction temperature was operated at only 85 A degrees C for OZCO. The reaction temperature of TCO operated above 270 A degrees C decomposed IPA at the same efficiency.
Applying Surface Charge Attraction to Synthesizing TiO2/Ag Composition for VOCs Photodegradation
(2013-10-01)
Lin, Yu-Chih
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Bai, Hsunling
;
Lin, Chia-Hsin
;
Wu, Jin-Fang
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環境工程研究所
This study utilized a unique method to prepare TiO2/Ag composites by operating the pH value of synthesis solution, which causes the opposite charges on the surface between TiO2 and Ag to enhance the combination affinity of TiO2 and Ag due to electron attraction. The results showed that the TiO2/Ag prepared in solution at pH 5.8 was characterized as high TiO2 dispersibility and the optimal combination between TiO2/Ag, due to the opposite surface charges and the greatest difference in zeta potentials between TiO2 and Ag. The prepared TiO2/Ag was utilized to process acetone photodegradation, and the results illustrated that TiO2/Ag prepared in solution at pH 5.8 showed the best performance in photodegrading acetone. With increasing TiO2 coated on Ag in TiO2/Ag, the photodegradation efficiency of acetone was enhanced. In terms of the average efficiency via TiO2 coating amount, 10 wt% was the most optimal efficient proportion of TiO2/Ag for the photodegradation of acetone.
Cushioning the pressure vibration of a zeolite concentrator system using a decoupled balancing duct system
(2007-07-01)
Chang, Feng-Tang
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Lin, Yu-Chih
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工學院
;
College of Engineering
A honeycomb Zeolite Rotor Concentrator (HZRC) is the main air pollution control device utilized by many semiconductor and optoelectronics manufacturers. Various plant exhaust streams are collected and then transferred to the HZRC for decontamination. In a conventional HZRC, the exhaust fan movement and the switching between different air ducts can cause significant duct pressure variations resulting in production interruption. The minimization (of pressure fluctuations to ensure continuous operation production lines while maintaining a high volatile efficiency is organic compounds (VOCs) removal efficiency essential for exhaust treatment in these high technology manufactures. The article introduces a decoupled balancing duct system (DBDS)for controlling the airflows to achieve a balanced pressure in the HZRC system by adding a flow rate control device to the VOCs loaded stream bypass duct of a conventional system. Performance comparisons of HZRC with DBDS and other airflow control stems used by the wafer manufacturers in Hsinchu Science Park, Taiwan are presented. DBDS system had been proved effectively to stabilize the pressure in the airflow ducts, and thus avoided pressure fluctuations; it beeped to achieve a high VOCs removal efficiency while ensuring the stability of the HZRC. (c) 2007 American Institute of Chemical Engineers Environ Prog, 26: 188-196, 2007.
Engineering stable Pt nanoparticles and oxygen vacancies on defective TiO2 via introducing strong electronic metal-support interaction for efficient CO2 photoreduction
(2020-06-01)
Lin, Liang-Yi
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Kavadiya, Shalinee
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He, Xiang
;
Wang, Wei-Ning
;
Karakocak, Bedia Begum
This work for the first time reports the promoting effect of strong electronic metal-support interaction (EMSI) in N/TiO2-V-O (V-O: oxygen vacancy) for gas-phase CO2 photoreduction. A novel in-situ surface hydrogenation was developed to prepare hydrogenated N/TiO2-V-O in a continuous, high throughput diffusion flame aerosol reactor. The combined results of various characterization techniques confirmed the presence of EMSI between N and defective TiO2-V-O resulted in the enhanced electronic density of N nanoparticles. Both the modulated electronic structure of N and surface oxygen vacancies simultaneously promoted the activation of surface adsorbed carbon intermediates and facilitated the separation of photogenerated charges, eventually boosting the photocatalytic activity of N/TiO2-V-O. The optimized N/TiO2-V-O demonstrated a high quantum yield of 1.49% with high CH4 selectivity (81%), which rendered 5.8- and 1.2-fold enhancements over its counterparts of TiO2-V-O and N/TiO2. More significantly, the EMSI also played a critical role in preserving the surface metallic Pt-0 and oxygen vacancies, and in sustaining high activity of the Pt/TiO2-V-O, whereas rapid catalytic deactivation are observed for both TiO2-V-O and Pt/TiO2.
Human Recognition Based on Kinematics and Kinetics of Gait
(2011)
Lin, Yu-Chih
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Yang, Bing-Shiang
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Lin, Yu-Tzu
;
Yang, Yi-Ting
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機械工程學系
Human recognition based on gait is a new biometric method that considers both spatial and temporal features which tracks the gait of a human being from a distance. The most widely used techniques for gait recognition at present can be divided into two categories: the model-free method and the model-based method. Both these methods process images of a moving body. Although some effort has been devoted to gait recognition, a high identification rate and low computational cost still need to be achieved. In this study, we investigated gait recognition in terms of biomechanics, which is often overlooked in the fields of computer science and electronics. We present a method for people recognition by using both the three-dimensional parameters for lower limb joints, i.e., kinematic and kinetic parameters. Dynamic data are acquired by tracking marker positions using a motion capture system with force plates. Although a marker-free and cable-free biometric system is more applicable for security purposes, acquiring data by marker tracking is one of the most precise methods currently available. The results obtained from marker tracking can clarify the relationship between the recognition rate and dynamic data of normal walking. In this study, 350 trials were conducted for 10 subjects. For each subject, 20 trials were conducted for training and the remaining 15 were for testing. A self-organizing map (SOM) neural network was employed for data classification. The importance of a specific variable in each dimension for each joint is discussed in detail to investigate the major factors that cause the differences in human gait according to a biomechanical approach. Experimental results showed that gait is a reliable feature for individual identification since a high recognition rate can be achieved by choosing appropriate joints or dynamic parameters in some dimensions of a gait. Kinematic variables in the frontal and transverse planes of the knee or hip joints are recommended due to their higher recognition rates. These findings can be applied to both biomedicine and computer science.
Optimizing operating parameters of a honeycomb zeolite rotor concentrator for processing TFT-LCD volatile organic compounds with competitive adsorption characteristics
(2009-05-30)
Lin, Yu-Chih
;
Chang, Feng-Tang
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工學院
;
College of Engineering
In this study, we attempted to enhance the removal efficiency of a honeycomb zeolite rotor concentrator (HZRC), operated at optimal parameters, for processing TFT-LCD volatile organic compounds (VCCs) with competitive adsorption characteristics. The results indicated that when the HZRC processed a VOCs stream of mixed compounds, compounds with a high boiling point take precedence in the adsorption process. In addition, existing compounds with a low boiling point adsorbed onto the HZRC were also displaced by the high-boiling-point compounds. In order to achieve optimal operating parameters for high VCCs removal efficiency, results suggested controlling the inlet velocity to <1.5 m/s, reducing the concentration ratio to 8 times, increasing the desorption temperature to 200-225 degrees C, and setting the rotation speed to 6.5 rpm. (C) 2008 Elsevier B.V. All rights reserved.
People Recognition by Kinematics and Kinetics of Gait
(2009)
Lin, Yu-Chih
;
Yang, Bing-Shiang
;
Yang, Yi-Ting
;
機械工程學系
;
腦科學研究中心
Human recognition by gaits is a new biometric method which considers both spatial and temporal features by tracking the gait at a distance. Most researches use image processing methods to analyze the moving object, while some use the model-based methods. Although some efforts have been devoted to the gait recognition, a high identification rate and a low computational cost still need to be achieved. This paper tends to investigate the gait recognition from the biomechanical point of view, which is lacking in the computer science and electronics communities. We present the method of people recognition by using both three-dimensional parameters of lower limb joints, namely, kinematic parameters (including joint angles and angular velocities) and kinetic parameters (joint forces). Dynamic data are acquired by tracking the maker positions using a motion capture system. 350 trials for 10 subjects are conducted, in which we use 20 trials for each one of these for training and the remaining 15 for testing. Additional 35 trials for another one subject not in the training set are conducted for testing the adventitious people. SOM neuron networks are employed for data classification. The importance of specific joints and variables is discussed in detail to investigate the major factors that cause the differences in human gait through a biomechanical approach. Experimental results show that gait is a reliable feature for individual identification since a high recognition rate can be achieved by choosing the proper joints or dynamic parameters of a gait. It also suggests that some joints and dynamic parameters dominate the differences in the walking style of people, which can be applied to both the biomedical and the computer vision fields.