• Title/Summary/Keyword: Geo-technology

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A Comparative Analysis for the Digitizing Accuracy by Satellite Images for Efficient Shoreline Extraction (효율적인 해안선 추출을 위한 위성영상별 디지타이징 정확도 비교 분석)

  • Kim, Dong-Hyun;Park, Ju-Sung;Jo, Myung-Hee
    • Journal of the Korean Association of Geographic Information Studies
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    • v.18 no.1
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    • pp.147-155
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    • 2015
  • The existing field survey and aerial photography involve the waste of manpower and economic loss in the coastline survey. To minimize these disadvantages, the digitization for efficient coastline extraction was conducted in this study using the points extracted from the standard coastline of the approximate highest high water and the diverse satellite images (KOMPSAT-3, SPOT-5, Landsat-8 and Quickbird-2), and the comparative accuracy analysis was conducted. The differences between the standard coastline points of the approximate highest high water and the coastline of each satellite were smallest for KOMPSAT-3, followed by Quickbird-2, SPOT-5 and Landsat-8. The significant probability from between the multipurpose applications satellite and Quickbird-2 (significant probability two-tailed) was statistically significant at 1% significance level. Therefore, high-resolution satellite images are required to efficiently extract the coastline, and KOMPSAT-3, from which images are easily acquired at a low cost, will enable the most efficient coastline extraction without external support.

Beach Deformation Caused by Typhoon Chaba in 2016 Along the Manseongri Coast Related Coastal Improvement Project (연안정비사업이 수행된 만성리 해수욕장에서 2016년 태풍 차바에 의한 해빈변화)

  • Park, Il Heum;Park, Wan-Gyu;Jeong, Seung Myong;Kang, Tae-Soon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.6
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    • pp.710-718
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    • 2017
  • After Typhoon Chaba (No.18, 2016) collided with Manseongri Beach, a coastal improvement project was carried out since strong external forces such as waves, storm surges and wave-induced currents were observed to cause beach deformation. The shoreline, beach area and beach volume were periodically surveyed. On the basis of this field data, the beach deformation that occurred at Manseongri Beach has been formally described. Over three months after beach nourishment work began, the beaches were gradually stabilized in terms of natural external forces. However, this stabilization was interrupted by Typhoon Chaba. After two months of typhoon weather, the beach returned to a stable state and no changes were observed until one year after the beach recovery work. Just after the typhoon hit, the shoreline receded from the northern side, where no reduction of external forces occurred, while the rear beach area submerged by breakwater advanced. Also, the beach volume decreased by $3,395m^3$ after the typhoon, due to erosion that occurred on the northern beach, with deposition taking place on the southern backshore area. Therefore, it has been concluded that the coastal improvement project undertaken at Manseongri Beach has significantly contributed to conservation in areas of wave-dominant sediment transport.

Water Depth and Riverbed Surveying Using Airborne Bathymetric LiDAR System - A Case Study at the Gokgyo River (항공수심라이다를 활용한 하천 수심 및 하상 측량에 관한 연구 - 곡교천 사례를 중심으로)

  • Lee, Jae Bin;Kim, Hye Jin;Kim, Jae Hak;Wie, Gwang Jae
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.4
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    • pp.235-243
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    • 2021
  • River surveying is conducted to acquire basic geographic data for river master plans and various river maintenance, and it is also used to predict changes after river maintenance construction. ABL (Airborne Bathymetric LiDAR) system is a cutting-edge surveying technology that can simultaneously observe the water surface and river bed using a green laser, and has many advantages in river surveying. In order to use the ABL data for river surveying, it is prerequisite step to segment and extract the water surface and river bed points from the original point cloud data. In this study, point cloud segmentation was performed by applying the ground filtering technique, ATIN (Adaptive Triangular Irregular Network) to the ABL data and then, the water surface and riverbed point clouds were extracted sequentially. In the Gokgyocheon river area, Chungcheongnam-do, the experiment was conducted with the dataset obtained using the Leica Chiroptera 4X sensor. As a result of the study, the overall classification accuracy for the water surface and riverbed was 88.8%, and the Kappa coefficient was 0.825, confirming that the ABL data can be effectively used for river surveying.

Exploiting GOCI-II UV Channel to Observe Absorbing Aerosols (GOCI-II 자외선 채널을 활용한 흡수성 에어로졸 관측)

  • Lee, Seoyoung;Kim, Jhoon;Ahn, Jae-Hyun;Lim, Hyunkwang;Cho, Yeseul
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1697-1707
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    • 2021
  • On 19 February 2020, the 2nd Geostationary Ocean Color Imager (GOCI-II), a maritime sensor of GEO-KOMPSAT-2B, was launched. The GOCI-II instrument expands the scope of aerosol retrieval research with its improved performance compared to the former instrument (GOCI). In particular, the newly included UV band at 380 nm plays a significant role in improving the sensitivity of GOCI-II observations to the absorbing aerosols. In this study, we calculated the aerosol index and detected absorbing aerosols from January to June 2021 using GOCI-II 380 and 412 nm channels. Compared to the TROPOMI aerosol index, the GOCI-II aerosol index showed a positive bias, but the dust pixels still could be clearly distinguished from the cloud and clear pixels. The high GOCI-II aerosol index coincided with ground-based observations indicating dust aerosols were detected. We found that 70.5% of dust and 80% of moderately-absorbing fine aerosols detected from the ground had GOCI-II aerosol indices larger than the 75th percentile through the whole study period.

A Study on Environmental Impact Assessment Guidelines for Marine Environmentsin Construction Projects of Offshore Waste Disposal Landfills (해상최종처리장 건설사업의 해양환경 환경영향평가 가이드라인 개발 연구)

  • Lee, Haemi;Son, Minho;Kang, Taesoon;Maeng, Junho
    • Journal of Environmental Impact Assessment
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    • v.28 no.3
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    • pp.312-331
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    • 2019
  • An offshore waste disposal facility refers to a landfill site for final landfilling of stabilized inorganic solid waste such as land and marine waste incineration materials, and the aim of such a facility is to solve the problem of insufficient waste disposal space on land and create and develop environmentally friendly marine spaces. The purpose of this study is to prepare guidelines for the construction of offshore waste disposal facilities, which reflect the need and importance of paying sufficient heed to environmental considerations from the initial stage of the project, in order to investigate, predict, and assess how such guidelines will affect the marine environment in relation to the construction of offshore waste disposal facilities, with the goal of minimizing the impact on and damage to the environment. For the purpose of this research, guidelines focusing on the construction of offshore waste disposal facilities were derived through an analysis of domestic cases and similar foreign cases and an assessment of their level of compliance with existing EIA guidelines through the operation of a discussion forum. In order to review the EIA report on similar cases in Korea, 17 EIA documents (2005~2016) for dredged soil dumping areas and ash ponds of thermal power plants were analyzed to investigate the status of marine organisms, marine physics, marine water quality, and marine sediment and to understand what types of problems can occur and what improvement measures can be taken. The purpose of these guidelines were to minimize damage to the marine environment by promoting EIA protocols in accordance with scientific and systematic procedures, to reduce the consultation period related to projects, to resolve social conflicts, and to reduce economic costs.

Determination of Location and Depth for Groundwater Monitoring Wells Around Nuclear Facility (원자력이용시설 주변의 지하수 감시공의 위치와 심도 선정)

  • Park, Kyung-Woo;Kwon, Jang-Soon;Ji, Sung-Hoon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.17 no.2
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    • pp.245-261
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    • 2019
  • Radioactive contaminant from a nuclear facility moves to the ecosystem by run-off or groundwater flow. Among the two mechanisms, contaminant plume through a river can be easily detected through a surface water monitoring system, but radioactive contaminant transport in groundwater is difficult to monitor because of lack of information on flow path. To understand the contaminant flow in groundwater, understanding of the geo-environment is needed. We suggest a method to decide on monitoring location and points around an imaginary nuclear facility by using the results of site characterization in the study area. To decide the location of a monitoring well, groundwater flow modeling around the study area was conducted. The results show that, taking account of groundwater flow direction, the monitoring well should be located at the downstream area. Also, monitoring sections in the monitoring well were selected, points at which groundwater moves fast through the flow path. The method suggested in the study will be widely used to detect potential groundwater contamination in the field of oil storage caverns, pollution by agricultural use, as well as nuclear use facilities including nuclear power plants.

Effect of Garcinia kola seeds supplemented diet on growth performance and gonadal development of Oreochromis niloticus juveniles breed in ponds

  • Nyadjeu, Paulin;Angoun, Jeannette;Ndasi, Ngwasiri Pride;Tabi-Tomedi, Minette Eyango
    • Fisheries and Aquatic Sciences
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    • v.22 no.9
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    • pp.20.1-20.8
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    • 2019
  • Background: Despite the favorable geo-climatic potential of Cameroon, the national production of tilapia remains low due to poor tilapia growth reported by fish farmers. One of the underlying reasons is the early female maturation at a very small size and precocious breeding in earthen ponds, resulting in overpopulation which leads to stunted growth and therefore to the production of unmarketable fish size. Studies have shown that dietary supplementation of G. kola enhanced growth in young Clarias gariepinus and Oreochromis niloticus. It was also reported that G. kola inhibited spawning in Tilapia adult females. Therefore, this study sought to assess the effects of Garcinia kola as growth promoter and inhibitor of gonadal development in young Oreochromis niloticus. Methods: A total of 108 juveniles weighing $13.32{\pm}0.62g$ were randomly distributed in 9 hapas of 12 fishes each (9 females and 3 males) and fed for 70 days with three isonitrogenous diets, 40% crude protein with increasing Garcinia kola supplementation levels of 0 (normal diet), 6% and 10% (experimental diets). Physico-chemical parameters of the water (temperature, dissolved oxygen, pH, nitrate, nitrite, ammonia, and transparency) were measured twice a week. Every 14 days, fish were harvested, counted, and weighed. At the end of the experiment, three fish of each sex per replicate were sacrificed and their gonad and liver collected and weighed. Data were statistically analyzed using one-way analysis of variance repeated measure followed by Newman-Keuls multiple tests. Results: The results showed that all physico-chemical parameters of the water were within the recommended values for Tilapia culture. Tilapia fed 6% Garcinia kola supplemented diet displayed higher final body weight in males ($38.60{\pm}3.50g$) and females ($36.77{\pm}3.62g$) compared to those receiving normal diet ($36.23{\pm}1.36g$ and $25.87{\pm}3.32g$; respectively to the final body weight in males and females). The gonadosomatic index and hepatosomatic index indicated no significant variation in males while in females, these were significantly low in the experimental fish compared to control fish. Conclusion: The results of this study demonstrated that supplementation of G. kola seeds in diets of young Tilapia improved growth performance and impaired gonadal development in females.

Review of China's National Earthquake Governance and Role-Sharing (중국 국가 지진 거버넌스 및 역할분담 고찰)

  • Kim, Seong-Yong
    • Economic and Environmental Geology
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    • v.54 no.1
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    • pp.127-136
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    • 2021
  • This study was carried out to understand China's earthquake governance and role-sharing, and to strategically use it for research cooperation in related fields with China. The characteristics of China's national earthquake governance and role-sharing are detailed in this study. First, unlike Korea, China's geoscience and earthquake research fields are separate, and are clearly distinguished from other fields of science and technology. They hold a higher status compared to other fields in China. Second, China's provincial earthquake agencies simultaneously carry out related tasks under the dual supervisory management system of the central and provincial governments. Third, the China Earthquake Administration (CEA) has the authority to do research and development, manpower training, and degree conferment, which are centered on directly affiliated institutions. Fourth, China carries out similar functions in directly affiliated institutions of the CEA and the China Geological Survey (CGS), and affiliated institutions of the Chinese Academy of Sciences (CAS), respectively. Fifth, the CEA is continuously expanding the seismic observation network that connects the vast land of the country. Sixth, China is considered to have detailed structures of earthquake-related laws and regulations. Given China's earthquake governance and role-sharing, it is considered that the possibility of success in research cooperation is high if Korea first determines whether it is under the jurisdiction of the CGS, CEA, and CAS, depending on the specific field.

Analysis of the Latest Trends in Mineral Resource Exploration and Mining in China and its Implications (중국의 광물자원 탐사개발 최신동향 분석 및 시사점)

  • Kim, Seong-Yong;Heo, Chul-Ho
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.1
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    • pp.75-81
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    • 2022
  • Given that China's resource research, exploration and development and resource economy policies are closely related to Korea's industrial competitiveness in the field of global mineral energy resources, it is important to establish the domestic and overseas resource development strategies. In 2020, China will revise and set standards for mineral resources to ensure efficiency in exploration and development and storage management. China's Ministry of Natural Resources has established the National Mineral Resources Plan (2021-2025), aiming to achieve national goals and strategies, and local governments at all levels are also establishing and implementing regional mineral resources plans. As a result, the supervision and management of geological mineral exploration activities have been strengthened, and the safety of industrial production management in the field of geological mineral exploration and development has been strengthened. China has developed guidelines for high-quality geological exploration, surveying and mapping, improved the level of geological mineral exploration and strengthened the mining supervision and management system. According to China's standardization of mineral resources such as solid mineral resources and petroleum gas mineral resources, a new standard system for resource management will be established in China to improve scientific understanding, rational management and utilization.

Research on the Necessity of Building the Second Space Rocket Launching Sites for Breakthrough Development of R.O.K National Space Power (도약적 국가 우주력 발전을 선도할 제2 우주센터 구축 필요성 연구)

  • Park, Ki-tae
    • Journal of Space Technology and Applications
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    • v.2 no.2
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    • pp.146-168
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    • 2022
  • Witnessing current military conflicts in South China Sea and Eastern Europe, most defense analysts evaluate one of the most serious security threat toward the US is coming from the superpower competitions with Russia and China. The main means for such super power hegemonic competitions is military power and space power is a key enabler to maximize the efficiency and effectiveness of military employment. Reflecting above circumstances, the space hegemonic competition between the Unites States and China is spreading into all aspects of national powers. Under such an environment, R.O.K needs to significantly develop national space power to preserve life and assets of people in space. On the other hand, the R.O.K has a lot of limitations in launching space assets into orbits by land-based space rockets due to its geographic locations. The limitation of rocket launching direction, the failure to secure a significant area enough to secure safety and the limitation to secure open area enough to build associated facilities are among them. On this paper, I will suggest the need to build the 2nd space rocket launching site after analyzing a lot of short-falls the current 'Naro' space center face, compared to those of advanced space powers around the world.