Browsing by Author "Ahmad Shukri Yahaya"

Now showing 1 - 9 of 9
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    Air quality predictions using log normal distribution functions of particulate matter in Kuala Lumpur
    (Environmental Management Society Malaysia, 2006) Jannatul Naemah Mohamed Sedek; Nor Azam Ramli; Ahmad Shukri Yahaya
    Malaysia's capital city of Kuala Lumpur has been developed from a small settlement at the confluence of the Klang and Gombak rivers into a vibrant and bustling metropolis. The associated rapid economic growths have started to impose costs in terms of industrial pollution and the degradation of urban environment. Air pollution is a major issue in this city that has been affecting human health, agricultural crops, forest species, and ecosystems. This paper reports findings of a research aimed at developing a tool needed to analyze the statistical characters of air quality data in Kuala Lumpur, Malaysia. In this study, the theoretical distribution Log Normal was used to fit the parent distribution of PM10 for 1998 and 2002 for Kuala Lumpur.
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    Boosted Regression Tree (BRT) Model for PM10 Concentrations Prediction in Malaysia
    (IOP Publishing, 2023) Norazrin; Hazrul Abdul Hamid; Ahmad Shukri Yahaya
    The aim of the study was to propose a Boosted Regression Tree (BRT) model for predicting PM10 concentrations in the short term. Multiple Linear Regression (MLR) and Boosted Regression Tree (BRT) models for short-term PM10 predictions are provided, and performance indicators (IA, R2, RMSE, MAE, and MAPE) are used to find the appropriate model. The Department of Environment Malaysia (DOE) provided seventeen years of daily average air quality monitoring data, including eight parameters (PM10, wind speed, temperature, relative humidity, NO2, SO2, CO, and O3) and five monitoring stations (Perai, Shah Alam, Nilai, Larkin, and Pasir Gudang).
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    Diurnal fluctuations of ozone concentrations and its precursors and prediction of ozone using multiple linear regressions
    (Environmental Management Society Malaysia, 2010) Nor Azam Ramli; Nurul Adyani Ghazali; Ahmad Shukri Yahaya
    The chemical reaction of pollutants emitted into the atmosphere leads to a variety of oxidized products, which are commonly referred to as secondary pollutants. Ground level ozone is a known secondary photochemical pollutant of major importance possessing detrimental effects on health, agriculture, natural/urban ecosystems and materials. Ozone (O3) can irritate lung airways and cause inflammation much like sunburn. Hourly and monthly variations of O3 and their precursors-nitrogen oxides (NOx) and meteorological parameters (temperature and wind speed) were presented using time series plots.
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    Future daily PM10 concentrations prediction by combining regression models and feedforward backpropagation models with principle component analysis (PCA)
    (Elsevier, 2013) Ahmad Zia Ul-Saufie; Ahmad Shukri Yahaya; Nor Azam Ramli; Norrimi Rosaida; Hazrul Abdul Hamid
    Future PM10 concentration prediction is very important because it can help local authorities to enact preventative measures to reduce the impact of air pollution. The aims of this study are to improve prediction of Multiple Linear Regression (MLR) and Feedforward backpropagation (FFBP) by combining them with principle component analysis for predicting future (next day, next two-day and next three-day) PM10 concentration in Negeri Sembilan, Malaysia.
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    Level of benzene concentrations emitted from motor vehicles in various sites in Nibong Tebal, Malaysia
    (Springer, 2011) Wesam Ahmed Al Madhoun; Nor Azam Ramli; Ahmad Shukri Yahaya; Noor Faizah Fitri Md Yusuf; Nurul Adyani Ghazali; Nurulilyana Sansuddin
    Benzene is classified as carcinogenic compound which is emitted mainly from cars. In this study, benzene was measured at various sites in Nibong Tebal (urban, suburban, town, and rural) of different traffic volume, and traffic counts were performed simultaneously. Monitoring was carried out during the morning and afternoon traffic peaks. The aim of this study is to monitor benzene concentration at several development sites with different traffic flow. The monitoring was done by using indoor air quality meter.
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    Monsoonal differences and probability distribution of PM10 concentration
    (Elsevier, 2010) Noor Faizah Fitri Md Yusof; Nor Azam Ramli; Ahmad Shukri Yahaya; Nurulilyana Sansuddin; Nurul Adyani Ghazali; Wesam al Madhoun
    There are many factors that influence PM10 concentration in the atmosphere. This paper will look at the PM10 concentration in relation with the wet season (north east monsoon) and dry season (south west monsoon) in Seberang Perai,Malaysia from the year 2000 to 2004. It is expected that PM10 will reach the peak during south west monsoon as the weather during this season becomes dry and this study has proved that the highest PM10 concentrations in 2000 to 2004 were recorded in this monsoon.
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    Satu tinjauan terhadap ujian-ujian kebagusan penyuaian
    (Penerbit UKM) Ahmad Shukri Yahaya
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    Statistical analysis of air pollution in the Klang Valley
    (UMS, 1999) Ahmad Shukri Yahaya; Noormala Mohd Yusooff
    The first part of this paper looks at the level of air pollution in the Klang Valley by considering two components of air pollutants that is suspended particulate matter and lead particles. The level of air pollution in traffic areas, commercial areas, industrial areas and residential areas were compared.The second part of this study, the analysis was concentrated on air pollution by heavy metals like plumbum (Pb), ferrum (Fe), cuprum (Cu), sodium (Na), calcium (Ca), aluminium (Al) and nickel (Ni). Factor analysis by principal component methid was used to identitfy the source of pollution by these heavy metals.
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    Statistical analysis of PM10 concentrations at different locations in Malaysia
    (Elsevier, 2011) Nurulilyana Sansuddin; Nor Azam Ramli; Ahmad Shukri Yahaya; Noor Faizah Fitri MD Yusof; Nurul Adyani Ghazali; Wesam Ahmed Al Madhoun
    Malaysia has experienced several haze events since the 1980s as a consequence of the transboundary movement of air pollutants emitted from forest fires and open burning activities. Hazy episodes can result from local activities and be categorized as "localized haze". General probability distributions (i.e., gamma and log-normal) were chosen to analyze the PM10 concentrations data at two different types of locations in Malaysia: industrial (Johor Bahru and Nilai) and residential (Kota Kinabalu and Kuantan).