Flood-hazard assessment and risk-based zoning of a tropical flood plain: Case study of the Yom River, Thailand [Evaluation du danger d'inondation et zonage basé sur le risque dans une plaine d'inondation tropicale: Cas de la Rivière Yom, Thaïlande]
Tingsanchali T.,Nakhon Pathom Rajabhat University |
Hydrological Sciences Journal | Year: 2010
This study contributes to the comprehensive assessment of flood hazard and risk for the Phrae flood plain of the Yom River basin in northern Thailand. The study was carried out using a hydrologic-hydrodynamic model in conjunction with a geographic information system (GIS). The model was calibrated and verified using the observed rainfall and river flood data during flood seasons in 1994 and 2001, respectively. Flooding scenarios were evaluated in terms of flooding depth for events of 25-, 50-, 100- and 200-year return periods. An impact-based hazard estimation technique was applied to assess the degree of hazard across the flood plain. The results showed that 78% of the Phrae flood-plain area of 476 km2 in the upper Yom River basin lies in the hazard zone of the 100-year returnperiod flood. Risk analyses were performed by incorporating flood hazard and the vulnerability of elements at risk. Based on relative magnitude of risk, flood-prone areas were divided into low-, moderate-, high- and severe-risk zones. For the 100-year return-period flood, the risk-free area was found to be 22% of the total flood plain, while areas under low, medium, high and severe risk were 33, 11, 28 and 6%, respectively. The outcomes are consistent with overall property damage recorded in the past. The study identifies risk areas for priority-based flood management, which is crucial when there is a limited budget to protect the entire risk zone simultaneously. © 2010 IAHS Press.
Tingsanchali T.,Nakhon Pathom Rajabhat University
Procedia Engineering | Year: 2012
Flood impact is one of the most significant disasters in the world. More than half of global flood damages occur in Asia. Causes of floods are due to natural factors such as heavy rainfall, high floods and high tides, etc., and human factors such as blocking of channels or aggravation of drainage channels, improper land use, deforestation in headwater regions, etc. Floods result in losses of life and damage properties. Population increase results in more urbanization, more impervious area and less infiltration and greater flood peak and runoff. Problems become more critical due to more severe and frequent flooding likely caused by climate change, socio-economic damage, population affected, public outcry and limited funds. Flood loss prevention and mitigation includes structural flood control measures such as construction of dams or river dikes and non-structural measures such as flood forecasting and warning, flood hazard and risk management, public participation and institutional arrangement, etc. This paper describes concepts, policy, plan and operation on integrated urban flood disaster and risk management. In most developing countries, flood disaster management activities are handled by government. Participation of nongovernmental agencies and private sectors are very limited. Activities are exercised rather independently without proper coordination or integration. Flood disaster management in developing countries is mostly reactive responding to prevailing disaster situations (emergency response and recovery). Reactive response should be changed to proactive response to increase effectiveness of management and reduce losses of life and properties. Proactive disaster management requires more participation from various governments, non-governmental and private agencies and public participation. It involves more effort and time, more budget, equipments, facilities and human resources which leads to integration of flood disaster management for both long term and short term activities. Strategic framework on integrated flood disaster management includes four cyclic steps namely: 1) preparedness before flood impact such as flood forecasting and warning; 2) readiness upon flood arrival; 3) emergency responses during flood impact and; 4) recovery and rehabilitation after flood impact. Examples on urban flood disaster and risk management in Thailand are illustrated and discussed. Conclusions and recommendations for further improvement are provided. © 2010 Published by Elsevier Ltd.
Janjai S.,Nakhon Pathom Rajabhat University
Procedia Engineering | Year: 2012
A number of students who are educated to be primary and secondary school teachers still have problems in designing lesson plans. In this research, an instruction model for improving the ability of students in designing the lesson plans was developed. The instruction model was based on the theories of constructivism and metacognition. The research activities consist of 4 steps as follows. Firstly, a learning unit was created by using the backward design approach. Secondly, an instruction model was designed by employing the theories of constructivism and metacognition. Based on this instruction model, the lesson plans of the learning units were prepared for teaching the students. Thirdly, 18 students of Nakhon Pathom Rajabhat University were taught by using this instruction model for one semester. Finally, the ability in designing the lesson plans of these students were evaluated. The evaluation was based on the achievement of the study and the quality of the lesson plans produced by these students. It was found that the ability in designing the lesson plans of the student after being taught by using this instruction model was significantly improved. In addition, the lesson plans obtained from 33.3%, 50.0% and 16.7% of the total students were evaluated to be in the very good, good and moderate levels, respectively. © 2010 Published by Elsevier Ltd.
Nathao C.,King Mongkuts University of Technology Bangkok |
Sirisukpoka U.,Nakhon Pathom Rajabhat University |
Pisutpaisal N.,King Mongkuts University of Technology Bangkok
International Journal of Hydrogen Energy | Year: 2013
Anaerobic digestion is an attractive process for generation of hydrogen and methane, which involves complex microbial processes on decomposition of organic wastes and subsequent conversion of metabolic intermediates to hydrogen and methane. Comparative performance of a sequential hydrogen and methane fermentation in two stage process and methane fermentation in one stage process were tested in batch reactor at varying ratios of feedstock to microbial inoculum (F/M) under mesophilic incubation. F/M ratios influence biogas yield, production rate, and potential. The highest H2 and CH4 yields of 55 and 94 mL g-1 VS were achieved at F/M of 7.5 in two stage process, while the highest CH4 yield of 82 mL g-1 VS in one stage process was observed at the same F/M. Acetic and butyric acids are the main volatile fatty acids (VFAs) produced in the hydrogen fermentation stage with the concentration range 10-25 mmol L-1. Little concentrations of VFAs were accumulated in methane fermentation in both stage processes. Total energy recovery in two stage process is higher than that in one stage by 18%. This work demonstrated two stage fermentation achieved a better performance than one stage process. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.
Chidthong R.,Nakhon Pathom Rajabhat University |
Hannongbua S.,Kasetsart University
Journal of Computational Chemistry | Year: 2010
The structural and electronic properties of fluorene-phenylene copolymer (FP)n, n = 1-4 were studied by means of quantum chemical calculations based on density functional theory (DFT) and time dependent density functional theory (TD-DFT) using B3LYP functional. Geometry optimizations of these oligomers were performed for the ground state and the lowest singlet excited state. It was found that (FP)n is nonplanar in its ground state while the electronic excitations lead to planarity in its S1 state. Absorption and fluorescence energies were calculated using TD-B3LYP/SVP and TD-B3LYP/SVP+ methods. Vertical excitation energies and fluorescence energies were obtained by extrapolating these values to infinite chain length, resulting in extrapolated values for vertical excitation energy of 2.89 and 2.87 eV, respectively. The S1 → S0 electronic excitation is characterized as a highest occupied molecular orbital to lowest unoccupied molecular orbital transition and is distinguishing in terms of oscillator strength. Fluorescence energies of (FP)n calculated from TD-B3LYP/SVP and TD-B3LYP/SVP+ methods are 2.27 and 2.26 eV, respectively. Radiative lifetimes are predicted to be 0.55 and 0.51 ns for TD-B3LYP/SVP and TDB3LYP/SVP+ calculations, respectively. These fundamental information are valuable data in designing and making of promising materials for LED materials. © 2009 Wiley Periodicals, Inc.