Browsing by Author "Chou, CC"

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A novel vision system for CRT panel auto-inspection
(2005)
Perng, DB
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Chou, CC
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Chen, WY
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工業工程與管理學系
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Department of Industrial Engineering and Management
The defects of a 3-D translucent hull CRT panel may include scratches, blemishes, cracks, bubbles, or collapsed portions. Defects may occur on the inside surface, outside surface, or interior of the glass. We designed and developed three sets of vision systems which can automatically inspect defects in CRT panels. The first system inspects the front-surface and two turn-segments, the second system inspects the other two turn-segments, while the third system inspects the side-wall defects. Two different kinds of lighting environments were developed to highlight the CRT panels and to simplify the image-capturing process. Meanwhile, a set of image processing methods were devised which can reliably detect the defects within the expected processing time. Experimental results demonstrate that the developed vision systems can be used to inspect CRT panels in the production line.
Characteristics of low-temperature-prepared (Ba, Sr)TiO3 films post treated by novel excimer laser annealing
(2002)
Shye, DC
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Chiou, BS
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Hwang, CC
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Chen, JS
;
Su, IW
Thin (Ba0.5Sr0.5)TiO3 (BST) films were sputtered on Pt[FiN/Ti/Si multilayer substrates at very low temperature (150degrees C). A novel process, using wavelength 248-nm KrF excimer laser annealing (ELA), has been undertaken to implement barium strontium titanate (BST) films at a low process temperature of 300degrees C. The crystallinity and dielectric constant are greatly improved after ELA treatment. In this work, the variation of texture was investigated. Besides, the escaped oxygen atoms from BST films were detected in-situ using a residual gas analyzer (RGA) during ELA process. Thus, the degradation of upper surface is strongly influenced by the laser energy fluence for an ELA-BST film.
Cyclic tests of post-tensioned precast CFT segmental bridge columns with unbonded strands
(2006-02-01)
Chou, CC
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Chen, YC
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土木工程學系
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Department of Civil Engineering
Two ungrouted post-tensioned, precast concrete-filled tube (CFT) segmental bridge columns were tested tinder lateral cyclic loading to evaluate the seismic performance of the column details. The specimens included a load stub, four equal-height circular CFT segments, and a footing. Strands were placed through the column and post-tensioned to provide a precompression of the column against the footing. One specimen also contained energy-dissipating devices at the base to increase the hysteretic energy. The test results showed that (1) both specimens could develop the maximum flexural strength at the design drift and achieve 6% drift with small strength degradation and residual displacement, (2) the proposed energy-dissipating device could increase energy dissipation in the hysteresis loops, and (3) the CFT segmental columns rotated not only about the base but also about the interface above the bottom segment. This study proposed and verified a method to estimate the experimental flexural displacement using two plastic hinges in the segmental column. Copyright (c) 2005 John Wiley & Sons, Ltd.
Maximum-likelihood estimation of frequency and time offsets in OFDM systems with multiple sets of identical data
(2006-07-01)
Cheng, MH
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Chou, CC
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電控工程研究所
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Institute of Electrical and Control Engineering
This paper generalizes the existing algorithm for the maximum-likelihood (NIL) estimation of frequency and time offsets in orthogonal frequency-division multiplexing (OFDM) systems using from two sets to multiple sets of identical data. The algorithm is derived by the application of the matrix inversion lemma; the Cramer-Rao bound for estimation of the frequency offset is also obtained. For reducing realization complexity, a simplified algorithm is developed. Simulations using the ten sets of identical data in the preamble of IEEE 802.11a for estimation of frequency and time offsets have been performed to verify the effectiveness of the proposed algorithms.
Performance evaluation of shear links and orthotropic bridge deck panels for the new San Francisco-Oakland Bay Bridge
(2005-04-10)
Uang, CM
;
Seible, F
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McDaniel, C
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Chou, CC
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土木工程學系
This paper presents results from testing and the associated analytical studies of steel shear links and orthotropic bridge decks to support the design of the new East Span for the San Francisco-Oakland Bay Bridge. Cyclic testing of full-scale built-up links showed that the specimens were able to reach an inelastic rotation more than twice that which would be produced from a 1500-year Safety Evaluation Earthquake event. Nevertheless, brittle fracture occurred before the inelastic design rotation capacity, as specified in the AISC Seismic Provisions, was developed. Based on a parametric study, a modification to the welding details was proposed, which proved to be effective in preventing this type of fracture in a subsequent testing program. Monotonic testing of two reduced-scale orthotropic bridge deck panels, one stiffened with closed ribs and another one with open ribs, also showed that these specimens could develop a compression capacity greater than that which would be produced by the design earthquake. The post-buckling behavior was associated with the buckling direction and the type of ribs. Copyright (c) 2005 John Wiley T Sons, Ltd.