Assessing Public’s Preferences and Willingness to Pay for Flood Prevention Program in Kuala Krai, Malaysia

Mahirah Kamaludin, A.A. Azlina, Jaharudin Padli and Roseliza Mat Alipiah

Page No. 1-10

The phenomenon of flood in Malaysia often occurs in the monsoon season that begins at the end of the year and continues until the early months of the next (November to March). The floods were caused by the increase of water level in the low-level areas as a result of continuous heavy rain. In order to prepare for the floods, which occur every year, considerable number of arrangements have been done by the government, particularly by the local authorities in the affected areas to reduce flood risks. The current practice of flood risk assessment concentrates on damages that can easily be measured in monetary terms; for instance, the tangible damages to assets that have market values.

However, the flood phenomenon is causing damages on assets that have no market values as well such as environmental impacts which are usually neglected. A study was carried out to estimate the publics’ willingness to pay (WTP) for flood prevention program with the aim of reducing the losses through contingent valuation method (CVM) by distributing questionnaires to 917 respondents. The study was carried out in Kuala Krai, Kelantan and concentrated in several flood-prone districts where the sample was randomly selected. The findings of the study demonstrate that the publics’ mean WTP is RM22.71 per month. The framework and findings of the study are expected to provide a guideline for researchers in the future with improvements in similar studies especially in Kuala Krai, Kelantan, Malaysia.

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Methodology on Landsat synthetic image generation under limited conditions

Soo Bong Lee, Yongmin Kim and Yang Dam Eo

Page No. 11-21

The data volume for satellite images that have been acquired and archived at present is in the petabyte range. In the future, more satellites will be launched and the number of acquired satellite images will increase exponentially.

Therefore, it is necessary to study the accumulated images. In this study, a large number of archived Landsat satellite images were used to produce simulated image at specific time. The simulation method consists of 1) the production of simulation image based on a similarity analysis and 2) the production of simulated image based on a case-based reasoning (CBR) approach which is a fusion of a similarity analysis and a statistical analysis. An accuracy assessment of the simulated images and the target image showed that 77% and 86% respectively of the pixels had correlation coefficients greater than 0.90 indicating a high accuracy for the proposed method. The proposed CBR method represents a new approach for simulating images by integrating a similarity analysis and a statistical analysis.

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Characteristics of the Horizontal and Vertical Response Spectra of the Pohang Earthquake (2017.11.15, ML = 5.4) Series

Jun Kyoung Kim, Tae Seok Oh, Yong Jeong Kwon and Jin Seok Noh

Page No. 22-31

The effects of earthquake magnitude and distance from the epicenter on the resonance frequencies of structures and buildings were explored using response spectra of 20 Pohang earthquake series including the main earthquake (2017/11/15; ML = 5.4). The spectra were compared to design response spectra based on the Regulatory Guide 1.60, 1973 (United States Nuclear Regulatory Committee) for Korean nuclear power plants and the Korean Building Code (KBC) code (2016) for general structures and buildings. A total of 660 horizontal and vertical accelerations from 11 seismic stations were used to derive the response spectra after normalization by reference to peak ground acceleration (PGA). The low-frequency response increased with distance from the epicenter, indicating that the response spectra were strongly dependent on distance. Additionally, our results revealed that it is necessary to consider distances > 200 km when exploring the frequency-specific characteristics of both low- and high-frequency bands of the design response spectra.

The response spectra exceeded those of Reg. Guide 1.60 above ~2 Hz depending on the conditions; thus, this regulation requires more stringent criteria to address higher frequencies. The horizontal response spectra of all six stations exceeded the KBC 2016 spectra (2,400-year return period; SE soil type) in almost all resonance bands after about 0.7 s, depending on soil type. Again, the design standards were inadequate. In terms of both Reg. Guide 1.60 and KBC 2016, the criteria should be modified to be more conservative over short periods i.e. high frequencies. Updated comprehensive design response spectra should be created by referencing large amounts of qualitative data from the Korean Peninsula on earthquakes of various magnitudes and their effects over a wide range of distances from the epicenter.

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A study on the Strategy of Green Roof Projects using Community Mapping Methodology

Jee Hee Koo, Ji Yeon Ahn, Jung Han Ha and Mu Wook Pyeon

Page No. 32-40

Many countries are trying to reduce greenhouse gas emissions through various policies. The National Assembly of Korea ratified the Paris Agreement, becoming the 97th nation to endorse the international pact and targeting 30% reduction from its BAU (business-as-usual) level by 2030. To this end, local governments develop various policies to implement projects to reduce greenhouse gas emissions and one of them is a green roof project.

In this study, we analyzed the green roof area and carbon absorption to propose a framework for local governments that can efficiently perform the green roof project. By voluntarily participating in the project selection and maintenance phases, we have built a community mapping-based system that provides citizens with information.

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Quantification of damage to RC Structures: A Comprehensive review

Hait Pritam, Sil Arjun and Choudhury Satyabrata

Page No. 41-59

A State of the Art review of damage indices of reinforced concrete (RC) structures has been discussed with their mathematical expressions of both local and global damage index (DI) in this paper. An extensive literature survey been carried out by the authors to know the current trends and limitations in these aspects. There are several techniques proposed by researchers for the estimation of DI of a structure to study the performance subjected to seismic loading.

This paper reviews the different schemes for classifying of damage indices attempted by the researchers so far. The available analytical and experimental procedures for the determination of damage indices are discussed. Based on the reviews made, the authors found some gaps/ limitations such as time dependent damage assessment, damage for different structural and non-structural components using different materials, variation of damage for different bay ratios need to be explored in future studies for better assessment of DIs with some essential directions for future research.

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