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۱Identification of Aerosol Sources Based on the Aerosol Optical Properties in Kuching, Sarawak
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنفرانس بین المللی پیشرفتهای علوم و تکنولوژی، سال
تعداد صفحات: ۱۰
Anthropogenic and natural aerosols are important atmospheric constituents that significantly contribute to the Earth’s radiation budget but remain uncertainties due to the poor understanding of aerosol properties and its direct effects on scattering and absoprtion of solar radiation. As the optical properties of aerosol particles were different for each particular time due to the short lifetime of the aerosols and basically could be linked closely by the sources of the aerosol. Different types of aerosols, representing biomass burning, urban or industrial pollution, maritime aerosols and dust particles will give different characterization and classification of aerosol properties itself. The aim of the study is to identify the sources of aerosol based on aerosol optical properties. Two parameters were used for aerosol analysis which are Aerosol Optical Depth (AOD) at wavelenght 440nm and Angstrom exponent derived from a multispectral log linear. The data used in this study were obtained from Aerosol Robotic Network (AERONET). To identify the sources of aerosol, the aerosol optical properties will be analyzed based on the characterization of aerosols which values of size radii close to zero will indicate coarse mode aerosols. Basically, these types of aerosol originated from sea spray and desert dust. Values of size radii for above 1.5 correspond to presence of fine–mode particles that originally comes from smoke or urban aerosols.The characterization had been done using scatter plot graph, then the types of aerosol will be classified based on dependency of AOD and Angstrom epxonent.After the characterization process, the aerosol will be classified based on dependency of AOT and Angstrom exponent also known as size radii. High density of AOD valuesand low Angstrom exponent values will corresponds to dust aerosols. High AOD density and high Angstrom exponent will indicate that the aerosol originated from anthropogenic sources.<\div>

۲THE AEROSOL LOADING FOR INLAND AND CLOSE–SHORE CITY DERIVES FROM URBAN ATMOSPHERIC MODEL
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنفرانس بین المللی پیشرفتهای علوم و تکنولوژی، سال
تعداد صفحات: ۹
Visibility degradation has become an environmental topic of community concern in most urban areas because of low visibility range that will lead to the deterioration of air quality. Atmospheric aerosol plays an important indicator of visibility distance range because it will influence the objects that can be seen. Microclimate can be defined as the climate of a small area such as part of a city. Inland city is the city located at interior of a country or region while close–shore city is the city that is surrounded by the sea or located near the sea. Both areas have different microclimate types.The objective of this study is to investigate the relationship of visibility range with atmospheric aerosol that can possibly be used as an indicator of air quality between the inland and close–shore city. The study used atmospheric model for urban aerosol algorithm in ATCOR2 PCI Geomatica to analyse the distribution of aerosols in terms of percent (%) reflectance. Landsat 5 Thematic Mapper images in Penang Island and Kuala Lumpur for the year 1993, 1999 and 2005 have been used to determine the aerosol loading. The atmospheric aerosol loading from the image was retrieved by different visibilities range at the distance of 10 km up to 50 km which are later converted into (%) reflectance. The mean reflectance values of a 3x3 pixel window were derived over urban features for both areas. The pattern of aerosol loading increased when visibility range is in between 10 to 20 km and decreased when visibility range is more than 30 km for both areas. In year 1993, the maximum aerosol loading was 9.7% in Kuala Lumpur and 15.1% in Penang Island. In year 1999, the highest aerosol loading was recorded at 11.3% in Kuala Lumpur and in Penang Island, the reading was 17.9%. The maximum aerosol loading showed in year 2005 was 10.1% in Kuala Lumpur and 20.0% in Penang Island. From the results, it shows that the aerosol loading for different atmospheric climates can be estimated using urban atmospheric model. The distance of the range of visibility can be used as an important parameter to determine the aerosol loading.<\div>

۳Wind Power Estimation from Forecast Wind Data
نویسنده(ها): ، ،
اطلاعات انتشار: ششمین کنفرانس بین المللی پیشرفتهای علوم و تکنولوژی، سال
تعداد صفحات: ۹
Efficient wind power production forecasting requires wind speed pattern study. Monthly wind data is insufficient to derive the pattern of wind speed. Long–term study of wind data was presented in this study to model the wind pattern. This study aims to estimate wind power from forecast wind data. Ten years of daily wind speed data set in Langkawi was used to retrieve the pattern of wind. Qualitative analysis used to study the annual characteristic of the wind. Several of time series models were tested with penalty function criteria method to identify the suit model. Forecast wind speed was derived from the model and thus wind power capacity was estimated by using kinetic energy formulation. Mean of annual data is 2.306 m\s and categorized as low wind speed with standard deviation 0.657 which means the wind speed was self–consistent. The suit model identified was Seasonal Autoregressive Integrated Moving Average (SARIMA) (1,1,3)×(1,1,1). Wind energy forecasted at Langkawi shows that the energy in Northeast monsoon is highest with average of9.61 Watts per second in a meter square.<\div>
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