• Journal of The Korean Association For Science Education
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• v.37 no.3
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• pp.465-481
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• 2017

This study is a research synthesis analyzing how field geology education is conducted in domestic and foreign countries in the recent 20 years and how it reflects the characteristics of authentic geologic inquiry. For these purposes, we first drew five elements of inquiry in field geology (observation, representation, abductive reasoning, spatial thinking, and diachronic thinking) considering the field geologists' actual research method as well as its pedagogical significance in science education. We developed analysis criteria for field geology education. The 53 cases were analyzed based on each element of inquiry in field geology and its sub-elements, and also the tendency of overall elements. As a result, observation and representation were included in most cases, but there appeared less frequency in order of abductive reasoning, spatial thinking, and diachronic thinking. For observation, the ratio of purposive observation and autonomous observation is high. For representation, both visualizing and linguistic type of representation and free-form representation appear frequently. For abductive reasoning, the step of generating hypothesis is often included and the hypothesis tends to be about the geological formatting process. For spatial thinking, type of self-location and perception of the spatial configuration of the structure appear at a high rate. For diachronic thinking, type of stratigraphic sequence is the most frequent. The proportions of the cases including three or more elements of inquiry in field geology consist 87% of the total. We suggested implications for improving geological fieldwork as authentic science inquiry in the future.

• Economic and Environmental Geology
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• v.55 no.6
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• pp.737-760
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• 2022

For the geological disposal of high-level radioactive wastes (HLW), an understanding of deep subsurface environment is essential through geological, hydrogeological, geochemical, and geotechnical investigations. Although South Korea plans the geological disposal of HLW, only a few studies have been conducted for characterizing the geochemistry of deep subsurface environment. To guide the hydrogeochemical research for selecting suitable repository sites, this study overviewed the status and trends in hydrogeochemical characterization of deep groundwater for the deep geological disposal of HLW in developed countries. As a result of examining the selection process of geological disposal sites in 8 countries including USA, Canada, Finland, Sweden, France, Japan, Germany, and Switzerland, the following geochemical parameters were needed for the geochemical characterization of deep subsurface environment: major and minor elements and isotopes (e.g., ³⁴S and ¹⁸O of SO₄^2-, ¹³C and ¹⁴C of DIC, ²H and ¹⁸O of water) of both groundwater and pore water (in aquitard), fracture-filling minerals, organic materials, colloids, and oxidation-reduction indicators (e.g., Eh, Fe²⁺/Fe³⁺, H₂S/SO₄^2-, NH₄⁺/NO₃^-). A suitable repository was selected based on the integrated interpretation of these geochemical data from deep subsurface. In South Korea, hydrochemical types and evolutionary patterns of deep groundwater were identified using artificial neural networks (e.g., Self-Organizing Map), and the impact of shallow groundwater mixing was evaluated based on multivariate statistics (e.g., M3 modeling). The relationship between fracture-filling minerals and groundwater chemistry also has been investigated through a reaction-path modeling. However, these previous studies in South Korea had been conducted without some important geochemical data including isotopes, oxidationreduction indicators and DOC, mainly due to the lack of available data. Therefore, a detailed geochemical investigation is required over the country to collect these hydrochemical data to select a geological disposal site based on scientific evidence.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.719-733
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• 2000

Normally, a digital geologic map can be defined as mappable one whose spatial information with geographic information details and geologic database attribute, recorded in a digital format that is readable by computer. It shows fundamentally two different conceptual perspectives: cartography for digital mapping and analysis for geo-data processing. While, as both aspects basically relate to natural entities and their interpretation of complex features fused with multi-sources, digital geo-data mapping or geologic mapping, it should be distinguished from digital mapping in engineering such as UIS(Urban Infomation System) and AM/FM(Automated Mapping/Facilities Management). Furthermore, according to short-cycled development of GIS(Geographic Information System) software architecture based on IT(Information Technology) and wide expansion of GIS applications' fields, the importance of domain analysis and application model is emphasized at digital geologic informatizaion. In this paper, first terms and concepts of geo-data model with general data modeling aspects are addressed, and then case histories for geo-data modeling and several approaches for data modeling in GIS application fields are discussed. Lastly, tentative conceptual geo-data modeling by using UML(Unified Modeling Language) of OO(Object-oriented) concepts with respect to USGS/AASG geo-data mode is attempted. Through this approach, the main benefits for standardization and implementation lineage with conceptual model in consideration to reusability are expected. Conclusively, it is expected that geo-information system and its architecture by UML is the new coming key approach for the GIS application in geo-sciences.

• Resources Recycling
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• v.33 no.3
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• pp.48-56
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• 2024

In this study, physical property evaluation and physical separation of the target product were performed to investigate the possibility of using sewage sludge gasification solid residue (GSRs) as a circulating resource. Firstly, the GSRs used in this study was supplied by Sudokwon Landfill Management Corporation, and generally the GSRs was in the form of porous pellets with a particle size of several millimetres. In addition, the partially black areas were confirmed to be unburned and ungasified carbon, and the average carbon content was 5%. In addition, the content of silica, alumina and phosphorus oxide was more than 70% of the total content. It was confirmed that the metallic components of the wet grinding product were separated into individual elements. As a physical separation of metallic and non-metallic components was required, it was finally found that flotation screening was suitable. Accordingly, cationic and anionic surfactants were selected to separate metallic components in which a relatively large amount of non-metallic components were concentrated, and the separation characteristics were confirmed. As a result, it is expected that the concentration of non-metallic components such as silica, alumina and phosphorus will be easier than the separation of metallic components. Therefore, since it is possible to physically treat the gasified sludge residue, it is judged to have potential as a circular resource according to the proposed recycling method for the separated product.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.207-211
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• 2008

In order to understand the difference in rice eating quality, two rice varieties having different eating qualities were examined from the correlation between palatability score (Toyo value) and components of lipid in rice endosperm. We also analyzed the relationship between lipid properties and physicochemical characteristics of milled rice. Major fatty acids of milled rice starch-lipids, known to exist as inclusion complexes with amylose in starch granules, were palmitic (38.25% in Gopum and 39.75% in Palgong) and linoleic aicds (33.13% in Gopum and 31.93% in Palgong). In addition, the unsaturated fatty acid contents of rice endosperm showed a significant relationship with palatability. Plant sterols in two rice samples were identified, Gopumbyeo of good eating quality had high contents of squlaene and cycloartenol and similar contents of campesterol, stigmasterol and sitosterol. There were significant differences in pasting properties of rice flours and starches between the two cultivars. These results suggested that rice lipids impact on pasting properties after cooking, subsequently relating to palatability.

• Journal of the Korean earth science society
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• v.26 no.3
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• pp.218-231
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• 2005

The purpose of this study was to investigate essential information about the geological and geomorphological characteristics of the Odaesan landscape, in order to efficiently preserve and develop resources selected from among that are highly valuable scholastically and esthetically. A total of 147 geological and geomorphological landscape resources were studied during the course of this study. Landscape type mostly discovered was the tectonic topography, followed by the topographies of weathering, river, mountain, lacustrine, and periglacier, respectively in decreasing order. Among the varieties of geological and geomorphological landscape resources, 4 outcrops were utilized as tourist resources and 5 outcrops were considered as valuable sites for scientific research. Geological and geomorphological landscape resources for academic research were considered to have practical uses such as geological and geomorphological fieldwork for students and thematic geotourism courses for the public.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.867-878
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• 2017

Recent interest in geological heritage has been increased in that it can be used as a basic data onto predicting the global environmental change of its containing information about past global environment. In addition, due to the characteristics of the geological heritage, it is easy to damage and difficult to recover without continuous preservation and management. However, there are more damages occurring because of the sporadic spatial distribution and ambiguous management authority of geological heritage. Therefore, an integrated management system is needed by determining the spatial distribution of geological heritage preferentially. In this study, the detailed criteria for assessment of value from the preliminary studies were applied and the geological heritage grade distribution map was generated by using geospatial data in Seoul metropolitan area. For this purpose, the list of geological heritage sites in the Seoul metropolitan area, which is the study area, were complied through a literature review. The geospatial database was designed and constructed by applying the detailed criteria for assessment of value from the preliminary studies. After the construction of the spatial database, a grade map of the geological heritage was created. As a result of the geological heritage grade map in the Seoul metropolitan area, there were more than 35% of the geological heritage in northern Gyeonggi provinces such as Yeoncheon city (18.8%), Pocheon city (10.6%) and Paju city (6.3%). It is followed by 18.1% in Incheon and 8.1% in Ansan, which is approximately 26.2% in western Gyeonggi Province. The geological age of the geological heritage was the highest at in the fourth stage of the Cenozoic era of 16.9%. Through the results of this study, the geological heritage data of the Seoul metropolitan area were extracted from existing literature data and converted into spatial information. It enables comparing the geological features with the spatial distribution of geological heritage. In addition, a management system has been established based on spatial information of constantly building geological heritage data. This provides the integrated management system of the geological heritage to manage authority so that it can be used as a basis for the development of the geological park. Based on the results of this study, it is considered to be possible to systematically construct and utilize the geological heritage across the country.

• Economic and Environmental Geology
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• v.41 no.6
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• pp.763-771
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• 2008

Uncertainties are pervasive in engineering geological problems. Therefore, the presence of uncertainties and their significance in analysis and design of slopes have been recognized. Since the uncertainties cannot be taken into account by the conventional deterministic approaches in slope stability analysis, the probabilistic analysis has been considered as the primary tool for representing uncertainties in mathematical models. However, some uncertainties are caused by incomplete information due to lack of information, and those uncertainties cannot be handled appropriately by the probabilistic approach. For those uncertainties, the theory of fuzzy sets is more appropriate. Therefore, in this study, fuzzy reliability analysis has been proposed in order to deal with the uncertainties which cannot be quantified in the probabilistic analysis due to the limited information. For the practical example, a slope is selected in this study and both the probabilistic analysis and the fuzzy reliability analysis have been carried out for planar failure. In the fuzzy reliability analysis, the dip angle and internal friction angle of discontinuity are considered as triangular fuzzy numbers since the random properties of the variables cannot be obtained completely under the conditions of limited information. In the study, the fuzzy reliability index and the probabilities of failure are evaluated from fuzzy arithmetic and compared to those from the probabilistic approach using Monte Carlo simulation and point estimate method. The analysis results show that the fuzzy reliability analysis is more appropriate for the condition that the uncertainties arise due to incomplete information.

• The Journal of Engineering Geology
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• v.27 no.4
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• pp.501-511
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• 2017

Natural radionuclides such as uranium and radon from 170 groundwater wells in Jeonnam Province were investigated, together with hydrogeochemical properties, and concentration maps of uranium and radon were also constructed in this study. Characteristics of their concentrations and occurrence were discussed using hydrogeochemical factors and geostatistical methods based on individual geological units. Though uranium and radon in groundwater show a wide range in the concentration, most of which occur as low levels except a few sites. Based on factor analysis, correlation coefficients between uranium and radon are very low. Such results verify that these radionuclides behave independently, well consistent with most previous results investigated nationwide in groundwater. Besides uranium and radon, most hydrochemical components in groundwater show a close relation to indicate the water-rock interaction taken place actively in aquifer.

• Economic and Environmental Geology
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• v.56 no.3
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• pp.217-227
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• 2023

Crystalline calcium carbonate (CaCO₃) occurs in various geological and aqueous environments as calcite, aragonite, and vaterite. These minerals also have practical applications in engineered settings. Synthetic methods of calcium carbonate have been developed for scientific research and technical applications. For example, these methods have become widely adopted for studying the formation of CaCO₃ minerals and (geo-)chemical processes involving these minerals in natural and engineered systems. Furthermore, these methods have the potential to be applied in various technical and biomedical fields. Water-based synthesis is particularly important for simulating the formation of calcium carbonate minerals in natural aqueous environments. This review paper describes the procedures and experimental conditions for water-based synthetic methods of each calcium carbonate polymorph, compares the morphological and structural features of the resulting crystals, and analyzes the crystallization mechanisms.