Tuan-Duc Nguyen

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In wireless distributed networks, cooperative relay and cooperative multiple-input-multiple-output (MIMO) techniques can be used to exploit the spatial and temporal diversity gains to increase the performance or reduce the transmission energy consumption. The energy efficiency of cooperative MIMO and relay techniques is then very useful for the(More)
Embedding a secret message into the pixels of a cover image yields a visual distortion if these pixels belong to smooth regions. Thus, this prompted the development of some edge-based approaches in which only the edge pixels are used to hide secret bits. As a result, the visual quality of stego images is improved. However, the capacity is limited due to(More)
Alamouti codes. The proposed technique combines two sequences of the received signal sampled at different times in order to perform an orthogonal combination. This technique has a better tolerance to the transmission synchronization error and also a low complexity. The significant advantage of using this new combination technique over traditional Alamouti(More)
In recent years, Wireless Sensor Network (WSN) is considered as a potential solution for real time applications in industrial automatic control. However, there are several challenges to develop real time WSN due to its wireless nature, limited resources (power, processing and memory), low node reliability and dynamic network topology. Several researches(More)
In the context of ubiquitous wireless sensor network, this paper presents a framework for wireless sensor networks (WSNs) designed to observe impacts of climate change in crop fields. We propose a system architecture for ubiquitous WSNs for monitoring automatically and continuously in real-time. A prototype system includes two base stations and several(More)
The computational complexity of matrix embedding (ME)-based steganography is high due to the use of the Hamming parity check matrix and matrix multiplication. Furthermore, with only one embedding change solution, ME cannot minimize embedding distortions when applied to joint photographic experts group (JPEG) steganography. In this paper, we propose a novel(More)