• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.1
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• pp.35-45
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• 2018

Image data collected by an airborne hyperspectral camera system have a great usability in coastal line mapping, detection of facilities composed of specific materials, detailed land use analysis, change monitoring and so forh in a complex coastal area because the system provides almost complete spectral and spatial information for each image pixel of tens to hundreds of spectral bands. A few approaches after classifying by a few approaches based on SAM(Spectral Angle Mapper) supervised classification were applied for extracting optimal land cover information from hyperspectral images acquired by CASI-1500 airborne hyperspectral camera on the object of a coastal area which includes both land and sea water areas. We applied three different approaches, that is to say firstly the classification approach of combined land and sea areas, secondly the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas, and thirdly the land area-only classification approach using atmospheric correction images and compared classification results and accuracies. Land cover classification was conducted respectively by selecting not only four band images with the same wavelength range as IKONOS, QuickBird, KOMPSAT and GeoEye satelllite images but also eight band images with the same wavelength range as WorldView-2 from 48 band hyperspectral images and then compared with the classification result conducted with all of 48 band images. As a result, the reclassification approach after decompostion of land and sea areas from classification result of combined land and sea areas is more effective than classification approach of combined land and sea areas. It is showed the bigger the number of bands, the higher accuracy and reliability in the reclassification approach referred above. The results of higher spectral resolution showed asphalt or concrete roads was able to be classified more accurately.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.2
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• pp.225-231
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• 2020

Fresh water that can be used by a person of the total amount of water on the planet is increased because it is less than 0.01 % except underground water, ice and snow, etc. water management response need. In order to protect and efficiently utilize water resources, major countries are conducting water footprint studies that can quantitatively estimate the amount of water put into the operating phase of the resource harvesting phase, mainly agriculture. Korea has also recently developed a number of policies in order to cope with water shortages, and in the construction industry, as well as the need for basic research to support it has been emphasized. This study was constructed DB up to the raw material harvesting step, the transport step, the production stage in order to estimate the water consumption of resources to be put into the work process to target the drainage of the road. Water usage estimation method was utilized the method presented in the Water Footprint Manual and the environmental score card certification guide, unit water usage each drainage main method was calculated after estimating the water footprint considering the water character factor, indirect water and the direct water, the water consumption factor of material input to each process. Brown asphalt, rebar, remicon of the drainage material as a result of the water footprint calculation accounted for 97 % of the total. Drainage method is a culvert, a side channel, a culvert wing wall, reinforced concrete open channel accounted for 92.2 % of the total. Drainage total step-by-step calculated water consumption and water footprint was found in order of raw material harvesting step, transport stage, production stage. Water footprint each drainage method or total drainage material calculated in this study can be used as a base data in the agricultural and construction sectors. In order to increase the reliability of the analysis, it is believed that further overseas databases will be needed for continuous review and research.

• Korean Journal of Mineralogy and Petrology
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• v.36 no.2
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• pp.135-145
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• 2023

Aggregate is used to produce stable materials like concrete and asphalt and is fundamental to meet the social needs of housing, industry, road, energy and health. A total of 42.35 billion tons of aggregate were produced in 2021 worldwide, an increase of 0.91% compared to the previous year. Among them, 2 billion tons were produced in China, India, European Union and United States, making up to 71.75% of the share. South Korea has witnessed a constant increase in aggregate production, overtaking Mexico and Japan for seventh place with 390 million tons and 0.85% of the share. The industrial sand and gravel produced globally amounted to 352.66 million tons. The top seven countries with the highest production were China, United States, Netherlands, Italy, India, Turkey and France, and their production exceeded 10 million tons and held a share of 74.69%. Exports of natural rock recorded $21.68 billion in 2021, increased by $2.3 billion compared to the previous year, while exports of artificial rock increased by $2.66 billion to $13.59 billion. Exports of sand reached $1.71 billion with United States, Netherlands, Germany and Belgium being the four countries with the highest exports of sand. The four countries exported more than $100 million in sand and took up 57.70% of the total amount. Exports of gravel totaled $2.75 billion, with China, Norway, Germany, Belgium, France and Austria in the lead, making up to 48.30% of the total share. The aggregate quarry started to surge in the 1950s due to the change in people's lifestyle such as population growth, urbanization and infrastructure delvelopment. Demand for aggregate is also skyrocketing to prevent land reclamation and flood caused by sea-level rise. Demand for aggregate, which was around 24 gigatons in 2011, is expected to double to 55 gigatons in 2060. However, it is likely that aggregate extraction will heavily damage the ecosystem and the world will eventually face a shortage of aggregate followed by tense social conflict.