Chih-Ming Wang

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—We investigate a technique for counterfeit detection of high-frequency radio frequency identification (RFID) cards based on the electromagnetic characteristics of the cards rather than the digital information that they transmit. We describe a method of quantifying the electromagnetic signature of an RFID card and identify a small set of features that is(More)
—Moving object extraction plays a key role in applications such as object-based videoconference, surveillance, and so on. The difficulties of moving object segmentation lie in the fact that physical objects are normally not homogeneous with respect to low-level features and it's usually tough to segment them accurately and efficiently. Object segmentation(More)
This paper presents an H.323 standard compliant virtual video conferencing system. The proposed system not only serves as a multipoint control unit (MCU) for multipoint connection but also provides a gateway function between the H.323 LAN (local-area network) and the H.324 WAN (wide-area network) users. The proposed virtual video conferencing system(More)
—We show that careful measurements of the unloaded resonance frequency and quality factor of radio frequency identification proximity cards allow identification of different card models and, for the set of cards we studied, identification with minimal error of individual cards of the same model. Furthermore, we show that card identification performance is(More)
We present measurements demonstrating that electronic calibration units are stable enough to be used in place of mechanical vector-network-analyzer verification artifacts. This enables a new fully automated approach to verifying microwave vector-network-analyzer calibrations with a single computer-controlled electronic verification artifact. The new system(More)
  • Qian Wang, Edward T F Rogers, Behrad Gholipour, Chih-Ming Wang, Guanghui Yuan, Jinghua Teng +1 other
  • 2016
Photonic components with adjustable parameters, such as variable-focal–length lenses or spectral filters, that can change functionality upon optical stimulation, could offer numerous useful applications. Tuning of such components is conventionally achieved by either micro-or nano-mechanical actuation of their constitutive parts, by stretching or heating.(More)