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Carbon nanotube (CNT) acts as electromagnetic interference shielding material in concrete composites was presented in this paper. Three concrete samples respectively with different CNT contents were casted and experimentally tested their shielding effectiveness (SE). The SE measurements which were obtained in function of frequency were taken using vector network analyzer (VNA) in the frequency range of 2.4 - 4.0 GHz. The experimental results showed that the CNT contributes to change in conductivity due to the positioning of the electric field of the incident wave and thus, produces different shielding performances. The EMI SE of concrete composites is improved up to 41dB with CNT concentration of 1.5-2.0 wt%.

EMI shielding technique by using appropriate shielding material in an enclosure is commonly effective to block signal penetration. This paper presents the investigations on EMI shielding effectiveness of multilayer carbon fiber composites for architectural shielding purposes. The properties of carbon fiber such as high thermal conductivity, corrosion resistant, high tensile strength and excellent EMI shielding property make it suitable to be applied in building construction. The concrete samples with insertion of carbon fiber sheets were undergone the EMI penetration test which is based on IEEE standard testing procedures. These customized structures are proven to reduce signal penetration significantly in the high frequency range up to 2 GHz.

This study denotes an effective design for thermal regulating by integrating the water-cooling system on photovoltaic (PV) panel. The efficiency of the PV module will reduce the increasing temperature on the panel. Thus, the focus of this study is to improve the efficiency of the PV module by maintaining a low operating temperature. A modification on the rear part of the PV panel is executed by integrating the water-cooling system by using copper pipe. This study is conducted to compare the effects of the PV panel when it is tested in different circumstances, such as with and without water-cooling system as well as a variation of water flow rates at constant solar irradiance. Comparative analyses are performed by conducting I-V and P-V curve as well as temperature test where both tests take these different conditions into account. The study exhibits that the utilisation of water-cooling system will result to a reduced rear temperature of the PV panel. The efficiency of the PV panel has also experienced an increase of 3% for 300 l/h flow rates compared to the one without water-cooling system. The increase of flow rates of the water-cooling system will reduce the rear temperature of the PV panel. In other words, a more massive reduction of temperature on the PV panel with 16°C is detected when the water-cooling system is utilised up to 300 l/h flow rates in 60 minutes duration at 350 W/m2 solar irradiance.

The number of cases involving human death has increased due to scattered virus in the air. This has become a major concern on air quality, especially indoor air quality. The chemical compounds found in the building have limited exchange of outdoor and indoor, which results in building of contaminants such as CO2 emitted by occupants activity in the building. The usage of air conditioner is unable to removes pathogens because its only circulates in air within the area. Medical Centre has a very high potential to centralize the patient with diseases related to health problems such as asthma, respiratory and cardiovascular related-diseases. This study is conducted at medical centre of NDUM, in Kuala Lumpur. The number of patients admitted was compared to the level of CO2, temperature and relative humidity in the Medical Centre. The outdoor air index is collected from DOE Malaysia. Wireless Sensor Network (WSN) is used in this system as it can collect and disseminate the environmental data. Zigbee with 2.4GHz band is used as the wireless standard for the measurement. Sensors were attached to several points at the wall of the waiting room and were controlled by the PC module. Lab View is used to manage the data acquisition due to its ability to program a real-time system. The collected data of temperature, relative humidity and level of C02 determined the indoor air quality in the medical centre. This study brought to the assessment on the medical practice and the air quality that met the standard suggested by ASHRAE.