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Phytoremediation is an environment-friendly and cost-effective method to clean the environment of heavy metal contamination. A prolonged phytotoxicity test was conducted in a single exposure. Scirpus grossus plants were grown in sand to which the diluted Pb(NO3)2 was added, with the variation of concentration were 0, 100, 200, 400, 600, and 800 mg/L. It was found that Scirpus grossus plants can tolerate Pb at concentrations of up to 400 mg/L. The withering was observed on day-7 for Pb concentrations of 400 mg/L and above. 100% of the plants withered with a Pb concentration of 600 mg/L on day 65. The Pb concentration in water medium decreased while in plant tissues increased. Adsorption of Pb solution ranged between 2 to 6% for concentrations of 100 to 800 mg/L. The Bioaccumulation Coefficient and Translocation Factor of Scirpus grossus were found greater than 1, indicating that this species is a hyperaccumulator plant. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this research is to develop a new affordable and sustainable green home which focusing on affordability of young generation to have their own house in early age of working. When housing affordability is measured by rent-income ratios based on annual income, affordability must be correlated with income. Moreover, housing will appear to be less affordable for the very young and very old; it will appear to be more affordable to households at the peak of their lifetime income profiles [1] (Quigley J.M & Raphael. S (2004). In addition with the nation''s need to fulfill the people housing needs, green sustainable living is also of importance to the government. With global concern on the environment and sustaining the world resources for the future generations, Malaysia has also embarked on initiatives for sustainable development. Green house is one of the best doable efforts that could be taken up for the cause. Incorporating rain-water harvesting system in the housing development is what this research is focusing on. This research then appraises the costing of materials for commercial housing development as possible avenue for cost reduction in the house price. Another element is the management of materials at construction site. It is hoped that out of this research a Commercially Affordable Sustainable House (CASH) module could be developed and later implemented for meeting the country''s housing needs and becoming an environmentally responsible country at the same time. [Copyright &y& Elsevier]

Abstract: Housing affordability research has been carried out by many as it is one of the key measures for a country''s socio-economy stability. This research is carried out to identify possible application of affordability measures including Price-Income Ratio (PIR) for measurement of first owned medium cost landed-house by the middle-income group in Malaysia. It is hoped that it could be seen as able to contribute to the ground knowledge and understanding on housing affordability for the middle-income group and variables that influenced the medium income group''s ability to own first medium-cost houses in Malaysia. [Copyright &y& Elsevier]

Locational Marginal Price (LMP) is one of the techno-economical indices in modern restructured power system. This paper represents the new approach to modeling large scale power system considering multi transmission lines per corridor and also, multi-generation units located at generation buses of power system. This approach is based on graph theory and incorporates an identical incidence matrix of the grid. Based on this methodology, system operator and planning entity could easily establish and operate the power system in an optimal manner. Incorporating a strong and flexible clearing market tool is one of the recent challenges in large scale power system. To overcome this challenge, we present an analytical approach based on graph theory in modeling the network and utilizing linear programming software in LMP calculation. One of the strongest features of this method is to reducing the computational memory needs and increasing the speed of reaching the optimal answers by implementing sparsity techniques. [ABSTRACT FROM AUTHOR]

Flood forecasting models are a necessity, as they help in planning for flood events, and thus help prevent loss of lives and minimize damage. At present, artificial neural networks (ANN) have been successfully applied in river flow and water level forecasting studies. ANN requires historical data to develop a forecasting model. However, long-term historical water level data, such as hourly data, poses two crucial problems in data training. First is that the high volume of data slows the computation process. Second is that data training reaches its optimal performance within a few cycles of data training, due to there being a high volume of normal water level data in the data training, while the forecasting performance for high water level events is still poor. In this study, the zoning matching approach (ZMA) is used in ANN to accurately monitor flood events in real time by focusing the development of the forecasting model on high water level zones. ZMA is a trial and error approach, where several training datasets using high water level data are tested to find the best training dataset for forecasting high water level events. The advantage of ZMA is that relevant knowledge of water level patterns in historical records is used. Importantly, the forecasting model developed based on ZMA successfully achieves high accuracy forecasting results at 1 to 3h ahead and satisfactory performance results at 6 h. Seven performance measures are adopted in this study to describe the accuracy and reliability of the forecasting model developed. [ABSTRACT FROM AUTHOR]

The epidemiology of infection by Plasmodium falciparum and P. vivax was investigated among Javanese migrants to an endemic region of Papua, Indonesia. A cohort of 243 migrants from Java was followed for malaria in a new settlement village in the endemic Armopa area of north-eastern Papua, beginning on the day each migrant arrived in the village. The subjects were monitored during home visits (three/week) and by the twice-monthly production of bloodsmears that were checked for malarial parasites. At the end of 33 months, 159 (65%) of the subjects remained under follow-up. The prevalence of parasitaemia in the village declined from 16% among those already living there when the study began in August 1996, to 5% when the study finished in June 1999. Over this period, 596 infections by P. falciparum and 723 by P. vivax occurred in the cohort, 22 and 27 of the subjects each experiencing at least six infections by P. falciparum and P. vivax, respectively. The incidence of malarial infection was higher during the first and second years post-migration (3.2 and 2.7 infections/person-year) than during the third (1.2 infections/person-year). Although the geometric mean parasite counts for P. falciparum increased over time (1209, 1478, and 1830 parasites/μl in the first, second and third years, respectively), the corresponding values for P. vivax (497, 535 and 490 parasites/μl) showed no such trend. Only one of the nine subjects who developed severe malaria (requiring intravenous quinine therapy) was a child, giving an odds ratio for a case of severe malaria being in an adult of 6.1 (P=0.08). [ABSTRACT FROM AUTHOR]

Flood is without doubt the most devastating natural disasters, striking numerous regions in Malaysia each year. During the last decades, the trend in flood damages has been growing exponentially. This is a consequence of the increasing frequency of heavy rain, changes in upstream land-use and a continuously increasing concentration of population and assets in flood prone areas. Malaysia, periodically, have faced with huge floods since previous years. Kelantan River basin, which located in the Northeast of Peninsular Malaysia, is prone to flood events in Malaysia. Kelantan River is the principal cause of flooding because it is constricted at its lower reaches. The capacity of the river at the downstream coastal area is less than 10,000 m3/s, therefore flood that exceeds this capacity will overspill the banks and discharge overland to the sea. Realizing the seriousness of the problems, it is vital in providing in time useful information for making crucial decisions especially to provide warning for any potential flood occurrence. In this study, stochastic flood forecasting model using stage regression method was applied to Kelantan River basin, in which the regression coefficients and equations was derived from the least square principle. The stochastic model were calibrated and validated which then shows that the equations derived are suitable to predict the hydrograph in Kelantan River basin. In conclusion, establishing a flood forecasting system would enhance the effectiveness of all other mitigation measures by providing time for appropriate actions. This has increased the importance of flood modelling for flood forecasts to issue advance warning in severe storm situations to reduce loss of lives and property damage.

This paper proposes a modeling approach for biodegradation of implant-bone scaffolds. A Computer simulation was performed to determine the wall shear stress (WSS) and permeability of simulated body fluid (SBF) with a constant flow rate of 0.025 ml/min. In this study, four morphological samples were used to immersion time from 0 to 72 hours. Each specimen was given a different bone strain (1000-3500 μstrain) which created a variation of displacement in the bone scaffold. The method used in the simulation was the fluid-structure interaction (FSI). The pressure drop through the specimen decreases linearly, the permeability increases as the porosity increases, and the mean wall shear stress decreases due to the length of the immersion time. It was obtained that the permeability values of the implant-bone scaffold increases from 7.79×10-10 m2 to 1.09×10-9 m2 and the mean shear stress values decrease from 2.86×10-3 Pa to 1.38×10-3 Pa.

The purpose of this study is to analyze the influence of morphology on the degrading behavior of porous magnesium bone scaffold by using computer simulation. Based on the experimental work, the three bone scaffold prepared with 30%, 41%, and 55% of porosity, respectively. The bone scaffold made of pure magnesium that immersed in simulated body fluid (SBF) for 72 hours with constant flow rates of 0.025 ml/min. After degradation, each specimen was scanned by μCT with a resolution of 17 μm. In this study, three different morphology before and after degradation was performed by computer simulation using the FSI method. Each specimen before and after degradation were given different bone strain (1000-3500 μstrain) that create displacement variations on the bone scaffold. Before degradation, the outcomes showed that the variation of displacement affects fluid characteristic change and for the specimen C (55% of porosity) generates the highest permeability with the value of 8.78 × 10-10 m2. After degradation, specimen A (30% of porosity) has a higher average shear stress of 2.04 × 10-3 Pa, specimen C (55% of porosity) has degradation rate of 3.37 mg/cm2/d and the highest porosity of 75.81%.