Managing potential health risks associated with drinking water supplies: some issues and approaches

More than 90% of Malaysia's water supplies are derived from surface water sources. Long-term monitoring programs and research data indicate that many river systems are moderately to grossly polluted by domestic and industrial wastes. Properly planned, long-term, interdisciplinary studies are needed to assess the health implications of the country's social and industrial development and the associated impacts on the quality of drinking water supplies. New areas of potential risks need to be properly evaluated and the multiple barrier concept in providing safe water supplies needs to be properly coordinated, instituted and continuously monitored

Characterization of beach sedimentary environments in the Batinah Region, Oman.

In this study, 252 surface sediment samples were collected for sand properties from three sites on the North Batinah coast: Harmul, North of Sohar industrial area, Majees South of Sohar industrial area and Zafaran 9 km South of Majees. Sampling was conducted in four occasions: November 2005, February 2006, June 2006 and November 2006. Almost, 52% of all samples were unimodal, 32% were bimodal and 16% were polymodal. June 2006 samples had a higher particle density than November 2006 samples. This is most probably due to rework and suspension, which lead to removal of light particles from the upper layer of the beach and high density particles to be concentrated in the bottom layer in June 2006 and deposition of light fraction of lower density in November 2006. Only Harmul samples had a significant difference between June 2006 samples and November 2006 samples in bulk density. The difference between the two sets in percentage water by volume was significant in Harmul and Zafaran but not in Majees. All sites showed significant difference between the two sets in percentage of air filled porosity and percentage of saturation. However, the sand pattern was the same in the three sites

Forecasting Malaysian overnight Islamic interbank rate using the Box-Jenkins model

Modelling the overnight Islamic interbank rate (IIR) is imperative to define the IIR performance as it would help the Islamic banks to adjust its costs of funding effectively and facilitate the policy makers to regulate a comprehensive monetary policy in Malaysia. The IIR framework which has been regulated by Bank Negara Malaysia under dual banking and financial system has always been overlooked in most previous studies in modelling the financial instruments rates. Therefore, it is vital to select the appropriate model as it resembles with the features of the IIR. The study assesses the forecasting performance of overnight IIR using the Box-Jenkins model. The suggested Box-Jenkins model has been applied to the Malaysian overnight IIR (in percentage) from 02/01/2001 to 31/12/2020. The empirical results determine that ARIMA (0,1,1) is the most appropriate model in forecasting overnight IIR as the model provides the smallest Mean Absolute Error (MAE), Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE). In multistep ahead forecasting, it can be summarised that ARIMA (0,1,1) model is able to trail the actual data trend of daily Malaysian overnight IIR up to 5-day ahead within 95% prediction intervals

The Improvement of first Iteration Log Periodic Fractal Koch Antenna with Slot Implementation

In this paper, a slotted is introduced at each of the radiating elements on the 1st iteration log periodic fractal Koch antenna (LPFKA). The antenna is designed to testify the appropriate performance at UHF Digital television which operates from 4.0 GHz to 1.0 GHz. The dimension of the conventional 0th iteration LPKFA is successfully reduced by 17% with the implementation of slotted. The results show a good agreement with a stable radiation pattern across the operating bandwidth, stable gain more than 5 dBi and reflection coefficient of below -10 dB over the desired frequency range

Screening of Aloe vera medium with different carbon and nitrogen sources for Lactobacillus acidophilus cultivation using fractional factorial design (FFD)

The aim of this research was to optimize the cultivation medium for economic production of a probiotic bacterium, Lactobacillus acidophilus using Aloe vera medium with different carbon (glucose, fructose and sucrose) and nitrogen (yeast extract, meat peptone, ammonium sulphate and urea) sources. Screening step was performed using 28 1/16 fractional factorial design (FFD) to investigate the significant effect of 8 factors used in this study on the biomass production expressed in log10 cfu/ mL. Biomass production was measured based on total plate count method for enumeration of viable cells. In the process of screening, the concentration range of Aloe vera, carbon and nitrogen used were from 1-2% (w/v), 1-2% (w/v) and 0.5-1% (w/v), respectively. The maximum biomass production was obtained with 11.816 log10 cfu/mL. It was shown that glucose, Aloe vera gel, combination of glucose and fructose and combination of glucose and ammonium sulphate were resulted significant (p <; 0.05) effect towards to the response, biomass production

Wideband textile antenna for wearable application

This paper describe the design simulation and fabrication of wideband textile antenna. A rectangular monopole planar antenna with h slot is proposed in this paper. The antenna is made from Fleece fabric as a substrate and Shieldit fabric material as conductive element of the antenna. The optimization of the design has been done using CST Software simulation. The simulated results show that the antenna is operating between 1.8 GHz and 5 GHz while the measured results is between 2 GHz and 4.5 Hz. The experimental are carried out in free space with different orientations of the antenna. The radiation pattern of the antenna is nearly omnidirectional. From the measurements results, the antenna can be used at 2.3 GHz and 3.5 GHz (WiMAX), 2.45 GHz (WiFi) and 2.6 GHz (LTE)

Commonality of rainfall variables influencing suspended solids concentrations in storm runoff from three different urban impervious surfaces

Finding a common set of rainfall variables to explain the concentration of suspended solids in runoff from typical urban impervious surfaces has many applications in stormwater planning. This paper describes a statistical process to identify key explanatory variables to Non-Coarse Particle (suspended solids<500 μm size) event mean concentrations measured from road, carpark and roof surfaces located in Toowoomba, Australia. The dominant variables for all surfaces were rainfall depth and peak 6-minute rainfall intensity. Storm duration, defined as the time period when rainfall intensity exceeds 0.25 mm/hr and antecedent storm rainfall were also important predictors, but was less dominant. The regression model fitted to non-coarse particle concentration across all surfaces was proportional to rainfall depth raised to a negative power and peak 6-minute rainfall intensity raised to a positive power; the proportionality constant varies by surface type. The form of this common model has a physical basis and is analogous to the Modified Universal Soil Loss equation widely used for soil loss estimation for non-urban areas

Series iteration of Fractal Koch antenna at UHF band

The design of Log Periodic Fractal Koch antennas at four different series of iterations are discussed in this paper. This technique is used to reduce the size of the antenna. In this works 0th iteration, 1st iteration, 2nd, 3rd and 4th series iteration have been applied to the antenna and the performance of the antenna on reflection coefficient, current distribution, radiation pattern and gain are compared and analyzed. The antennas have been designed and simulated using Computer Simulation Technology (CST) software. The FR-4 is used as a substrate material which has dielectric constant 4.6 and tangent loss 0.019. About 31.4% reduction of the antenna size has been achieved by using the 4th series iteration of fractal Koch technique with the other characteristics of the antennas are maintain with the standard dipole log periodic antenna