Browsing by Author "Chou, TC"

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A novel card-type transponder designed using retrodirective antenna array
(2001)
Chung, SJ
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Chou, TC
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Chiu, YN
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電信工程研究所
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Institute of Communications Engineering
A novel card-type 5.8 GHz passive transponder is designed for possible use in the Dedicated Short-Range Communication (DSRC) systems and/or the RF/ID systems. Four LHCP microstrip antennas are arranged in the transponder by using the Van Atta retrodirective design so that the transponder possesses the advantages of both a high responding signal level and a wide range of responding angles. Measurement results show that the present transponder produces a signal level 12 dB higher than a transponder with single-antenna design, while maintains the same range of the responding angles as the single-antenna one. Finally, by incorporating 8-bit test codes in the beacon (or interrogator) and in the transponder, the downlink and uplink performances of the transponder are demonstrated.
Effect of boundary conditions on the hydraulic behavior of geotextile filtration system
(2001-12-01)
Shan, HY
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Wang, WL
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Chou, TC
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土木工程學系
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Department of Civil Engineering
There are several test methods available for studying the behavior of geotextile/soil filtration systems. However, there has not been a consensus on which one of these methods should be the most appropriate. In this research, gradient ratio (GR) tests and hydraulic conductivity (HCR) tests were performed to evaluate the effects of boundary conditions on the behavior of geotextile/soil filtration systems. The test results show that the hydraulic conductivity of the filtration systems decreased as the effective stress and hydraulic gradient increased. Furthermore, the hydraulic conductivity obtained from GR tests with a hydraulic gradient of 5 could be taken as the lower bounds for HCR test results. Therefore, it is suggested that the GR test can be used to obtain reasonable and conservative design parameters of the filtration systems. (C) 2001 Elsevier Science Ltd. All rights reserved.
Studies on damage removing efficiency of B-11(+) and BF2+ implanted Si0.84Ge0.16 epilayers by rapid thermal annealing
(1996-01-08)
Chen, LP
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Chou, TC
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Chien, CH
;
Chang, CY
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電控工程研究所
High quality metastable pseudomorphic Si1-xGex epilayers were grown by ultrahigh vacuum chemical vapor deposition using Si2H6 and GeH4. These epilayers were implanted with 40 keV B-11(+) and 100 keV BF2+ ions at a dose of 1 x 10(15) ions/cm(2) and then annealed by rapid thermal annealing (RTA) processes at temperatures of 600, 650, 700, and 750 degrees C for 30 s duration. Double-crystal x-ray diffractometry was used to evaluate the level of the implant-induced damage and the damage removing efficiency of both ion implanted samples at different RTA conditions. The results show that the RTA process is more effective at removing damage from B-11(+) implanted samples than from those implanted with BF2+. (C) 1996 American Institute of Physics.