Advanced Materials Research Vols. 931-932

Abstract: The Lower Mekong River overflows regularly in rainy season which benefits the area in terms of agriculture and fishery. A critical extreme flood, however, can occur once in a while which can be catastrophic. Therefore, the ability to accurately predict extreme events using a simple but accurate flood forecasting method is crucial. The Muskingum flood routing method with average lateral inflow was used for the Lower Mekong River at Chiang Khan as monitoring site and Nong Khai as target site. Five historic flood hydrographs were used for lateral inflow evaluation. Another 4 were used for forecast testing. The results are very encouraging.

Abstract: Site dynamic characteristics evaluation of fundamental ground frequency, F_o and amplification factor, A_o in Senggarang region were presented in 2D and 3D contour maps (microzonation maps) based on the ambient noise measurements carried out using Lennartz 1 Hz tri-axial seismometer sensors. Reliability of F_o and A_o determined from the ambient noise technique has become the main key components in seismic hazard analysis, resonance effect assessment, predictions of sedimentary layer and shear wave velocity, through cheaper, non-destructive and quick methodology. 73 points of ambient noise records were analyzed using Horizontal-to-Vertical Spectral Ratio (HVSR) method in the boundary area of 800 m x 800 m with the grid spacing of 100 m x 100 m. Significant peaks of mean HVSR curves were checked against the criterions proposed by the SESAME guideline. Slight difference of the F_o contours pattern between the North-South (NS) and the East-West (EW) directions was observed, but vice versa to the A_o contours between both directions. Significant peaks of F_o values were distributed from 1.61 to 6.35 Hz, whereas the A_o values were found from 3.18 to 9.39. Wide gap between the ranges of F_o and A_o in respective direction have shown to the variation of sediment thicknesses. Meanwhile, dominance shape of significant peak from the HVSR curves may indicate to a large velocity contrast presence underneath the ground surfaces.

Abstract: Efficient urban infrastructure interventions make it possible to pursue goals of sustainable mobility, that nowadays are extremely important in light of the need to reduce the negative impact produced by human activities on the environment. In addition and to a no lesser extent, the implementation of the investment requires the monetary resources to realise the works. In relation to this aspect, the scarcity of public funds in the current economic contingency makes the involvement of private capital and entrepreneurial skills indispensable in the execution and performance of these works.This work shows how the use of a suitable economic evaluation model is indispensable in order to encourage public-private partnerships aimed at the execution and correct management of an intervention in the field of sustainable mobility. The proposed evaluation model implements the instrument of inter-sectorial matrices, which allow to determine the impacts (output) generated by a change in aggregate demand (input, such as the investment costs in an industry) on the economy of the territory where the matrix is associated.The analysis and calculations are carried out in relation to the project for the construction of a mechanical vector in the town of Vietri sul Mare in the province of Salerno (Italy), which is useful in ensuring the decongestion of road traffic and the consequent reduction in travel times along the Amalfi Coast.

Abstract: Subsurface drainage systems are widely used in agricultural area, when waterlogging and salinity are problems. Subsurface system can also help increasing the potential for infiltration. In this work, an application of subsurface drainage integrated with the decontamination system using activated carbon is proposed as a mean to recharge groundwater during the flood. Concern over the potential contaminating groundwater with urban runoff could be eliminated by the pretreated system incorporated with the recharging unit. A small model of the subsurface system envelope was tested to verify the activated carbon as a potential filled material. The result showed that the slope of the perforated pipe posed little or no effect on the flow rate in pipe due to the size of the model. For this preliminary study, it is highly possible to use activated carbon as filled material in subsurface systems for recharging groundwater.

Abstract: The disastrous flood that inundated many areas of the Chao Phraya basin in 2011 caused many detrimental effects on the countrys economy and society. It is vital for all concerned to better plan and manage these effects in order to minimize future disasters areas. Flood reduction requires water flow detention or deceleration of during the storm water season. The construction of water detention ponds is one solution that should be taken into account. This study investigated the reduction of water flow in Yom basin (a sub-basin of Chao Phraya basin) using the synthetic unit hydrograph to synthesize deluge parameters. The objectives of this case study are to utilize natural lowland areas upstream of Yom Basin, namely Bung Takreng, Bung Kheerang, and Bung Raman. These three swamps are adjacent to one another, so one detention pond system could be constructed. The relationship between volume (S) and height (H) of the detention pond system was found to be S=18866224.8H^1.15 based on the analysis of elevation data using Geographic Information System (GIS). The estimated inflow to the detention pond at different return periods was based on the synthetic unit hydrograph. The maximum flow rate was analyzed by flood routing through a modeled reservoir system. The reservoir system was assigned a 3 m height dyke over the spillways, dividing into 2 m for the peak drainage and 1 m freeboard. Flood routing was performed at the return periods of 2, 5, 10, 25, 50, and 100 years. We obtained the following safe lengths of spillway: 30, 70, 100, 140, 175, and 210 m, respectively. The detention pond system can detain water for 4 hr and reduce the peak flow in Yom River to 81.83, 84.44, 77.26, 81.00, 90.81, and 89.81m3/sec or 9.37, 5.75, 4.08, 3.30, 3.15, and 2.71 percent, respectively. Findings of this study can be applied in decision making regarding the construction size of the reservoirs. In addition, the results can be applied in developing other areas into detention ponds.

Abstract: Fractured rock aquifers provide the most extensive groundwater resources in Northeast Thailand. The hydraulic conductivity (K) of these aquifers controls the flow of water and is therefore, an essential parameter for groundwater modeling and management. K values may be directly determined by conducting pumping tests at the aquifer or by performing fracture analysis using data acquired from outcrops. The K value at outcrop should be greater than that at aquifer of deeper position due to the effect of aperture reduction by overburden compression. The goal of this study was therefor to find the correlation between K values determined from outcrop with those directly measured at an aquifer. This study was conducted on the Phu Phan sandstone aquifer at the Huay Luang watershed, Udon Thani Province of Northeast Thailand. The orientation, aperture, and spacing of fractures were measured at four outcrops and used for determining the K values by fracture analysis. Single well pump test data from 17 wells in the Phu Phan aquifer (30-120 m depth) were analyzed to obtain transmissivity (T) and K. Both sets of the K values, from outcrop and aquifer, were correlated using the plotting position of Weibull. Both plots were linear on a semi-log scale but the outcrop curve was steeper. Lognormal distributions fitted both plotting positions quite well. These results show that for the same probability value, K values found from the pumping test to be about an order of magnitude smaller than K values determined from outcrop data.

Abstract: The aim of this study is to assess the groundwater balance in the Yom basin by the MODFLOW model. The Yom basin is one of the main basins in Thailand that has no dams or reservoirs for collecting surface waters. Therefore, the general agriculture practice is using water from rainfall, pond or groundwater resources. Groundwater has been used too much especially in low land areas for agriculture and water supply. There are two sub-groundwater basins within the Yom basin. They are the Phare and upper Chao Phraya groundwater basin.The simulation area of Phare and upper Chao Phraya groundwater basins are 10572 and 13046 square kilometers respectively. The model design for both groundwater basins a utilized 1000 meters grid spacing and five layers of ground level (gravel, sand, clay and flint). Parameters of model are recharge rate, groundwater uses, water surface and aquifer hydraulic parameters. As a result, total groundwater of Phare groundwater basin is 440 million cubic meters and total groundwater of upper Chao Phraya groundwater basin is 517 million cubic meters. Total groundwater of Yom basin is 957million cubic meters and there is groundwater storage within the Yom basin of about 14688 cubic meters. Groundwater simulation can be utilized to provide information for water resource management in the future.

Abstract: Recycling of the nutrient solution used to irrigate fruit and vegetables in greenhouses can increase water use efficiency and reduce the contamination of local water sources. The nutrient solution cannot be recycled without treatment because of potential contamination of the entire plant system with bacteria, viruses, and/or fungi. Ozonation, pasteurization and chemigation are the typical techniques used, but are often expensive and not always effective [. Slow sand filter (SSF) is a technology that is relatively inexpensive to purchase and operate. Data was collected from two SSF to verify treatment efficacy and associated hydraulic characteristics. The SSF was able to consistently produce water with a turbidity less than 1 Nephelometric Turbidity Units (NTU) and with the infiltration capacity to treat 0.27 m³ m^-2 h^-1 of greenhouse effluent; which, equates to treating 3,600 L d^-1 of drainage water from a 1,000 m² greenhouse. The recovery rate for the filter was an average of 110 minutes. Ideal growing conditions for bacteria responsible for the treatment of the water in the SSF included warm and consistent water temperature, high nutrient content, and organic loading in the water. The SSF was able to sustain the hydraulic loading rate of 0.27 m³ m^-2 h^-1 for 16 days. At the end of this period the organic layer that was present at the sand/water interface reduced the infiltration rate because of the formation of the Schmutzdecke layer (SL). An air/water jet cleaning system scoured the SL and suspended it so that it could be drained.

Abstract: Water level prediction for supporting the right decision making is crucial. The study of daily gage height in Lam Phi-Kun Canal provides essential information to plan for flood prevention and hydroelectric generation of this canal. Daily gage heights in 2011 were used as training instances. We forecasted the gage heights for year 2012 using four different predictors, namely, Linear Regression, Multilayer Perceptron, MLPDQ1 and MLPDQ2. The latter two algorithms are named after our improvements to the existing Multilayer Perceptron by introducing a concept of time-dependent data division and a concept of weight adjustments of the polynomial trend line. Our proposed algorithms are implemented in Java language. The performance evaluation reveals that our two algorithms have distinctly smaller errors than the traditional two predictors. The average errors of our algorithms are less than one meter. We recommend our algorithms for other applications such as rainfall forecasting, sediment forecasting, sales forecasting, and energy consumption trends.

Abstract: This work aimed to investigate the potential of plastic waste in old landfill as a resource to produce pelletized RDF. Old landfill contents at different ages of 4-5, 5-10 and over 10 years old were excavated and sorted. The combustible part consisted mostly of plastics at 34.0, 21.9 and 22.1% at younger to the older age in order. The non-combustible part composted of soil-like material from 63.8 to 76.3% which made up of daily cover soil and organic debris. High calorific value of the plastic waste of 33.11-43.41 MJ/kg was not diluted by the mixing of binder. Heated compaction method was used in the formation of RDF pellets in this study. Bulk density was linearly increased with higher compaction pressure (R² = 0.9655). Besides, the vertical compressive strength of the formed pellets increased by 82 kg/cm² when the compaction pressure changed from 7 to 21 kg/cm² and started to decrease when it was above 21 kg/cm². Meanwhile the horizontal compressive strength was rather stable and appeared independent of the compaction pressure. Calorific value of the RDF produced was high because no binder of lower calorific value was used, enabling it to meet the specified European standard for its calorific value.