No abstract

Wireless sensor networks can be widely applied for a security system or a smart home system. Since some of the wireless remote sensor nodes may be powered by energy storage devices such as batteries, it is a very important issue to transmit signals at lower power with the consideration of the communication effectiveness. In this paper, we will provide a fuzzy controller with two inputs and one output for received signal strength indicator (RSSI) and link quality indicator (LQI) to adjust transmission power suitably in order to maintaining a certain communication level with a reduced energy consumption. And we will divide the sampling period of a sensor node into four intervals so that the sensor node radio device does not in receiving or transmission status all the time. Hence the sensor node can adjust transmission power automatically and reduce sensor node power consumption. Experimental results show that the battery life can be extended to about 10 times for the designed sensor node comparing to a normal node.

The prevalence of video recording capability, either on surveillance systems or mobile devices, has contributed to the popularity of video data. As a result, video management has become relatively more important than before and, in particular, video retrieval has been one of the main issues in this regard. Traditional video retrieval systems take texts as the inputs to look for similar information from the title, annotation or embedded textual data of a video, in a way that is very similar to the keyword search adopted by a common search engine. However, the lack of visual information specification during a search often makes the result rather inaccurate or even useless. For this reason, video retrieval systems using images or videos as the inputs have also been proposed; nevertheless, the associated ambiguity and complexity have made the implementation of such systems relatively difficult and, therefore, those systems are not as successful as desired. To address this, in this paper, we propose to perform a video retrieval of a desired object through the inputs of its trajectory and/or appearance, together with the help of a 3-D graphical user interface for more intuitive interactions, so that more satisfactory results can be achieved. We firmly believe that such a framework could serve as the foundation for behavior analysis used in many surveillance systems.Index Terms-Object reidentification, object tracking, video retrieval. 1051-8215