Chao-Lieh Chen

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In this paper, a feature-based robust digital image watermarking algorithm is proposed to achieve the goal of image authentication and protection simultaneously. The Hessian-Affine feature detector is at first adopted to extract characteristic regions of an image in the proposed watermark embedding scheme. Then the copyright watermark is embedded into these(More)
An effective, efficient and distributed fuzzy control algorithm is proposed to perform control over the contention parameters in the IEEE 802.11 media access control (MAC) layer for supporting quality of service (QoS) in wireless communications. The proposed fuzzy control algorithms reserves bandwidths by controlling the delays of mobile nodes in the(More)
This paper proposes an energy-proportional routing (EPR) algorithm, which effectively extends the lifetimes of clustered sensor networks. To optimally utilize energy, light-load clusters that conserve energy are ideal candidates as intermediate nodes for forwarding data from others. To balance the load, first, the proposed algorithm predicts energy(More)
We propose a dynamic fuzzy logic control (DFLC) for further enhancement of the IEEE 802.11e enhanced distributed channel access (EDCA) function. Although legacy IEEE 802.11 was enhanced by the 802.11e, in wireless networks real-time traffics over the IEEE 802.11e suffer unacceptable quality especially when network state is dynamic. We adopt fuzzy logic for(More)
Type reduction of interval type-2 (IT2) fuzzy sets is essential in conducting the type-2 fuzzy sets expressed with the resolution forms of IT2 fuzzy sets. Several type reduction methods, such as KM, EKM, and centroid flow, have been proposed. These methods are relatively easy to implement but still computationintensive because they need to invoke an(More)
Digital image watermarking is widely used for copyright protection of digital information. The effectiveness of a digital watermarking technique is indicated by the robustness of embedded watermarks against various attacks. So watermarking algorithms normally prefers robustness. Because of a robust algorithm it is not possible to eliminate the watermark(More)