Nadeeka Premarathna

University of Kelaniya · Department of Mathematics

Polyaromatic hydrocarbons (PAHs) released from vehicular emissions and oil refineries deposit on the phyllosphere, compromising the quality of leaf-based food products by posing many health issues. Nevertheless, the tea phyllosphere harbours a variety of endophytes that are highly effective at degrading polyaromatic hydrocarbons, anthracene, and py...

Flood is the most common natural disaster in Sri Lanka. Therefore, it is important to identify future flood-prone areas to mitigate damages caused by a flood. The present study was carried out for a selected area of the Attanagalu Oya basin situated in the Gampaha district for flood forecasting. The two software packages Hydrologic Engineering Cent...

Dengue fever, which is a rapidly spreading mosquito-borne viral disease, has become a major public health problem in the world, including Sri Lanka. The Western Province of Sri Lanka has been experiencing a very high number of Dengue incidences throughout the past few decades. According to literature, considerations have not been paid on the dynami...

Dengue fever is a rapidly spreading mosquito-borne viral disease, which is caused by the Dengue virus. It has become a major public health problem in the world, including Sri Lanka. Dengue is transmitted only through the bites of the infected mosquitoes. The number of mosquito bites during a certain period of time is therefore directly proportional...

Control chart procedures for monitoring paired variables are sparse in the literature. After considering the average run length properties of the chart, which monitors the mean of the differences between paired variables, we propose a new chart based on Sd, the subgroup standard deviations of the differences. Our findings show that the chart is pow...

Purpose The purpose of this paper is to investigate the applicability of Shewhart methodology and other quality management principles to gain a deeper understanding of the observed volatility in stock returns and its impact on market performance. Design/methodology/approach The validity of quality management philosophy in the context of financial...

The likelihood ratio test for testing simultaneous homogeneity of main effects of several factors against ordered alternatives in multifactor designs has been developed in the literature. But the level probabilities needed to implement these tests have been computed only for the 2-way layout. We use these results to calculate critical points for te...