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In current tsunami prevention and mitigation, evacuation is the most important method of saving people’s lives. Tsunami evacuation is analyzed for a given travel time and a specific inundation area. Before evacuation analysis, the tsunami inundation and tsunami travel time are first calculated by numerical modeling. This paper analyzes the tsunami evacuation of Haimen Town, Jiaojiang District, Taizhou City, China, under the hypothesis of a magnitude 9.0 earthquake scenario in the Ryukyu Trench. The Cornell multi-grid coupled tsunami (COMCOT) model and Tsunami Travel Time (TTT) model are used to calculate the tsunami inundation and tsunami travel time, respectively. GIS techniques are used to solve the evacuation problem. Both horizontal and vertical evacuations are adopted based on the Chinese community characteristics, disaster prevention facilities, land use, and other practical conditions. A cost raster is used to analyze the arrival cost of each grid in the study area. The location allocation and cost allocation methods are used to solve shelter selection and coverage problems, respectively. The network analyst is applied to provide evacuation routes for each community. The evacuation analysis results can provide a scientific reference for the development of tsunami evacuation plans.

Accurate river channel and flood plain representation plays vital part in flood risk analysis. Terrain models such as TINs and DEMs are normally used to represent floodplains. But unfortunately finding a terrain model with a high density of stream channel elevation points that are sufficient for hydraulic modeling is not a easy task. However for years engineers and researchers have developed a high-resolution cross-section data for hydraulic modeling from field surveys, photogrametries and topographic maps. This research presented here introduces the procedures for creating integrated multiresolution TIN (ITIN) models for highresolution flood plain representation for flood risk analysis. The high-resolution river channel geometric data stored in HEC-6 hydraulic model and low-resolution flood plain data in the form of DEM created in Arc View GIS 3.2a were integrated by resolving the coordinate incompatibility in the both system. An integration procedure (ArcView extention) namely AVHEC6.avx has been developed between HEC-6 Hydraulic Model and ArcView GIS 3.2a to visualize model outputs in a more presentable manner through 3D capabilities of GIS.

South Africa is a vast country, and there are significant variations in building material prices across the country. This chapter will use Geographic Information System (GIS) technology in explaining the role of distance in the differentiation in building material prices in South Africa. The research employs a quantitative research approach based on a cross-sectional survey research design and GIS technology in analyzing the data collected from each location. It emerged from the study that when distributed by provinces, the relationship between price and distance varies between inverse and direct. For example, while the price of clay bricks increases with distance in the Gauteng and KwaZulu-Natal provinces of South Africa, it decreases in the distance from the manufacturers in Western Cape province. The same ambivalent relationships are observed between timber, steel, bitumen, cement prices and distance. Based on these findings, the study concludes that the distance of a building material manufacturer from the retailer is not a predictor of price in the Western Cape province of South Africa, while the most uniform relationship is found in KwaZulu-Natal province. Further studies are therefore required to explain the other extraneous factors responsible for the irreconcilable retail prices of building materials in the Western Cape province when compared to other locations in South Africa.

The integration of building information modelling (BIM) and geographic information system (GIS) has been studied for a long period of time by researchers from both domains. The foundation of the integration is the interoperability of the data, which means the BIM data has to have a right reference system, allowing it to be read correctly by GIS software applications. 3D models from the BIM world may not be correctly georeferenced, which impairs the data interoperability. Instead of rebuilding models from scratch, which is time- and labour-consuming, this paper proposes a more efficient, economical, two-step alternative mainly based on Affine transformation. In the first step, the modification is made against the x- and y-coordinates. A number of control points would be selected to form displacement links. Based on these, the transformation parameters would be calculated, and the 2D footprint of the model would be rectified by Affine transformation. Then, the z-value (height information) of each vertex in the model would be adjusted using the scaling factor f. This method could obtain a 3D model without a geographical coordinate system correctly geo-referenced, and thus, it could be further read by GIS applications, consuming the vast spatial analysis tools supported by the GIS world, achieving more than just visualization. The key to the success of this study is creating an accurate right footprint of the model and selecting appropriate control points to guarantee the accuracy of transformation. By far, this approach has only been tested with a bridge model, its performance on other building models needs to be further studied.