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Nowadays, the demands on the usage of wireless network are increasing rapidly from year to year. Wireless network is a large scale of area where many nodes are connecting to each other to commun icate using a device. Primarily, wireless network also tend to be as a link to transmit and receive any multimedia such as image, sound, video, document and etc. In order to receive the transmitted media correctly, most type of media must be compressed before being transmitted and decompressed after being received by the device or else the device used must have the ability to read the media in a compressed way. In this paper, a hybrid compression of Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) with Huffman encoding technique are proposed for Wireless Sensor Network (WSN) application. Data compression is very useful to remove the redundant data and reduce the size of image. After conducting a comprehensive observation, it is found that hybrid compression is suitable due to the process consist of the combination of multiple compression techniques which suits for Wireless Sensor Network's application focusing on ZigBee platform.

In this paper, an approach to the shielding effectiveness evaluation of a metallic enclosure with off-centred apertures is discussed. It has been previously shown that a simple analytical transmission line formulation gives good predictions of the shielding effectiveness of a metallic enclosure with off-centred apertures. In this work the model is extended to include higher order modes in the transmission line (TL) models. The loading effect of electronic components within the enclosure is modelled by the introduction of losses. The model remains very simple and computationally efficient.

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Public believed that radiation leakage from microwave ovens was similar to atomic radiation that could lead to serious health problems, including cancer. For many years up to now, domestic microwave ovens were not considered to leak levels of microwave radiation that caused concerns; consequently, they have not been regularly monitored. According to Australian Standard 3301, the maximum allowable leakage from a microwave oven is 5 mW/ cm² at 5 cm distance from the oven surface. These safety standards were based on the belief that the only danger from exposure to high intensity microwave energy is a thermal or overheating effect. Since the leakage from microwave oven becoming a new issue, this paper is proposed to investigate the effect of oven leakage, the issue of emission levels versus exposure levels and the application of power density measurements in order to measure the leakage from microwave ovens. There are six measurements have been conducted and it is found that all of the microwave ovens are having leakage. From the measurement results, only one microwave oven gives a value of 10.19 mW/cm 2 which is exceeded the limit of 5mW/cm². Due to this reason, ti is suggested to use Conductive Transparent Film to reduce the leakage from the microwave oven, since it is a relevant way in shielding to prevent unwanted leakage from the microwave oven. The result shows that the Conductive Transparent Film can reduce the microwave oven leakage by about 12.39 dB to 8.53 dB.

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A 2.45 GHz active integrated ZigBee RFID system embedded with GPS is developed with an automated switching protocol algorithm utilizing wireless sensor network (WSN) platform to track the physical belongings or people in indoor and outdoor environments within a control area. In addition, to make the system contactless when the tag is not joining the network, the function of global system for mobile (GSM) communication is added to the integration. The communication between RFID reader and RFID tags is via WSN platform that supports mesh network and self-healing mechanism. Energy efficiency, robustness, and reliability are key factors in the design algorithm of the system. Comparisons are made between the existing active RFID system and the proposed active RFID system to study the performance of the proposed RFID system with an automated switching algorithm implemented on it. Based on the experimental study and statistical analysis done for all situations, a conclusion has been made where the proposed embedded RFID tag provided better signal propagation compared to the existing RFID tag and the battery lifetime for embedded RFID tag with switching mechanism is better than without switching mechanism. Recently, most of the researchers focused on the tracking such as buses, containers, logistics, vehicles, humans, and assets only for indoor or outdoor environment [2-10]. However, little has been done in the tracking of both Indoor and outdoor location especially using WSN platform [6]. Due to this reason, the embedment between RFID, GPS, GSM, and WSN is the main contribution part and the automated switching algorithm is implemented to facilitate indoor and outdoor location tracking simultaneously as presented in previous work [11]; thus this new paper is a continued work from the previous publication in [11]. The algorithm developed includes multimode configuration;