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Abstract. Uncontrolled issues of disposal waste tire rubber create huge environmental impact and health hazards. An alternative viable solution to minimize these problems is by utilizing the waste rubber tires in construction materials, which in turn can reduce the use of natural resources and eventually lessen the cost of construction. This paper mainly focuses on the use of waste rubber tires particles in concrete with different set of composition ranging from 3 to 12% of cement replacement. Concrete cubes size of 150mm x 150mm x 150mm were prepared for compressive strength test, and concrete cylinders size of 150m x 300mm were prepared for splitting tensile test. The result shows that the compressive and split tensile strength of concrete with rubber as cement replacements is 6-21% lower than the normal concrete.

Abstract. Energy is a catalyst for national development; most of the countries depend on hydrocarbon fuels for power generation. The traditional sources of energy are exorbitant and finite. In addition, they emit excessive carbon dioxide and other gases into the lower layer of the atmosphere, which influence the increase occurrence of global warming in the world. Recently, renewable energy's are gaining more attraction and attention in many parts of the globe, due to nonpolluting characteristics. Among the renewable, wind power has emerged as safest and cleanest resource that will satisfy the need of energy in a cost effective way. Wind energy system can suit the energy need for grid and stand-alone mode. This paper investigates the potential of wind energy in Kuching for small-scale power application. The study employed three years wind speed data spanning from 2010-2012 observed at the Kuching meteorological station. Details of the analysis carried out and potential of using wind energy systems are presented. Additionally, the output performances of two wind turbines are examined based on the computed Weibull distribution. IntroductionWind is a reliable, clean source of energy and the main opponent of fossil fuels because of the emission-free characteristics. In recent times, considerable attention has been devoted to utilizing the abundant resources. The merits of using this type of zero-emission energy when compared to other renewable energies, wind power can operate during the day and night time, and does not require numerous accessories, unlike solar power. Rapid development, urbanization, and population growth make renewable energy grew to be well known and recognized in the entire world. The substantial utilization of hydrocarbon energy sources has enhanced the generation of greenhouse gasses and other polluting materials; moreover, the resources are finite since they reduce after some spans [1][2][3].Wind can produce clean resources of electric power in the environment: residential and industrial areas. In addition, wind is a guaranteeing useful resource that can serve zero-emission energy to non-urban and remote residents in non-grid mode conveniently. Though, vertical axis wind turbines (VAWT) have been demonstrated to perform excellently in the quiet windy areas [3][4][5][6]. However, horizontal-axis wind turbines (HAWT) are frequent and widespread installed wind turbines. Nowadays, HAWT aerodynamics is also admired for low wind speed areas. One study [5] verified the feasibility of installing two small wind speed driving generators, for the lagoon of Venice in Italy, using 2-years anemometry measurement performed within study area.Wind flow is site specific and deviates with time and locations. To take advantage of the energy content in the wind by means of small wind drive systems successfully, the average annual wind speed and Weibull distribution are precondition requirements that are essential to the setting up

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Wind energy is a reliable, clean source and has emerged as one of the dependable, and the best performing developing renewable energy around the world. It has insignificant environmental impacts, compared to other energy sources. In Sarawak, Malaysia, wind resource varies depending on the location. An inadequate number of wind stations are the major obstacles that slow down the growing of green energy in the region. Site selection is a crucial issue for potential investors and policy makers. This paper examines the spatial distribution and the amount of potential wind power and energy densities for wind energy production and suitable locations in Sarawak. A geographical Information System (GIS) assisted methodology, which includes wind speed, power and energy densities using the existing wind station and based on the newly developed prediction model called topographical neural network (TNN) were used. Kriging interpolation was employed for a simple interpolation of data between locations. The results show that the northeast, northwest and coastal regions have better prospects of wind energy. The studied GIS methodology can be applied for identification of the most suitable locations for wind energy harvesting. The developed maps can further be used in micro-siting and economic evaluation analysis.

Night air temperature in Malaysia is generally about 23°C and is a potential source of heat sink to dissipate heat gain from a building. A thermal storage tank was used to store a certain quantity of water and was passively cooled during the night using the pitched roof as a heat exchanger to chill the water to as low as 22°C. The free cooling of water was then used as a cooling medium to cool the modular radiant cooling panel during the day time when the outdoor temperature exceeds 30°C. The experiment shows that the system was able to maintain an indoor temperature of less than 28°C when the outdoor temperature peaked to nearly 34°C while providing acceptable thermal comfort with certain controlled air movement. The use of the hydronic radiant cooling panel with free night cooled water as its coolant is proven to have significant energy saving potential of up to 85% while at the same time provide an acceptable room thermal comfort which meets the international standard criteria such as the American Society of Heating, Refrigerating and AirConditioning Engineers (ASHRAE) Standard 55.

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