• The Journal of Engineering Geology
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• v.32 no.4
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• pp.449-466
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• 2022

The establishment of a complete geological model that includes information about all the various components at a site (such as underground structures and the compositions of rock and soil underground space) is difficult, and geological modeling is a developing field. This study uses commercial software for the relatively easy composition of geological models. Our digital modeling process integrates a model of Jeju Island's 3D geological information, models of cave shapes, and information on the state of a road at the site's upper surface. Among the numerous natural caves that exist in Jeju Island, we studied the Jaeamcheon lava tube near Hallim town, and the selected site lies below a road. We developed a digital model by applying the principles of building information modeling (BIM) to the cave (CaveBIM). The digital model was compiled through gathering and integrating specific data: relevant processes include modeling the cave's shape using a laser scanner, 3D geological modeling using geological information and geophysical exploration data, and modeling the surrounding area using drones. This study developed a global-scale model of the Hallim region and a local-scale model of the Jaeamcheon cave. Cross-validation was performed when constructing the LSM, and the results were compared and analyzed.

• The Korean Journal of Quaternary Research
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• v.17 no.2
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• pp.145-148
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• 2003

The Kunang cave paleolithic site is located at Tanyang [$N37^{\circ}2'$, $128^{\circ}21'E$], Chungbuk Province, which is in the Central part of the Korean peninsula. The cave is developed at 312 amsl in a karstic mountainous area. The South Han River flows across this region and other caves can also be found near the river. The site was discovered in 1986 and excavated 3 times by the Chungbuk National University Museum until now. The cave was wellpreserved from modem human activities until the first discovery. The full length of the cave is estimated to be ca. 140 m. However, a spacious part up to 11 m from the entrance has been excavated. Eight lithological units are divided over the vertical profile at a depth of 5 m. Each unit is deposited in ascending order as follow: mud layer (Unit 9), lower complex (Unit 8) which is composed of angular blocks and fragments with a muddy matrix, lower travertine layer (Unit 7； flowstone), middle complex (Unit 6; cultural layer) which is composed of fragments with a muddy matrix, middle travertine layer (Unit 5； flowstone), yellowish muddy layer (Unit 4), upper complex (Unit 3； cultural layer) which has a similar composition to Unit 8. the upper travertine layer (Unit 2； flowstone), and finally surface soil layer (Unit 1). The most abundant vestiges in the cultural layers are the animal bones. They are small fractured pieces and mostly less than 3 cm in length. About 3,800 bone pieces from 25 animal species have been collected so far, 90 percent of them belonging to young deers. Previous archaeological study of these bone pieces shows thatprehistoric people occupied the cavenot for permanent dwelling but for temporary shelter during their seasonal hunting activity. More extensive studies of these bones together with pollen analysis are in progress to reconstruct the paleoenvironment of this cave. Only a single date (12,500 BP) obtained from a U-Th measurement of the upper travertine layer was previously available. In spite of the importance of the cave stratigraphy, there was no detail chronological investigation to establish the depositional process of the cultural layers and to understand the periodic structure of the cave strata, alternating travertine floor and complex layers. We have measured five 14C age dating (38900+/-1000, 36400+/-900, 40600+/-1600, more than 51000 and 52000 14C BP) using Seoul National University 14C AMS facility, conducted systematic process of the collagen extraction from bone fragments samples. From the result, we estimate that sedimentation rate of the cave earth is constant, and that the travertine layers, Unit 2 and Unit 3, was formed during MIS 5a(ca. 80 kBP) and MIS 5c (ca. 100 kBP) respectively. The Kunang Cave site is located at Yochonli of the region of Danyang in the mid-eastern part of Korea. This region is compased of limestones in which many caves were found and the Nam-han river flows meanderingly. The excavations were carried out three times in 1986, 1988, and 1998.

• Journal of the speleological society of Korea
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• no.7
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• pp.15-24
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• 1998

Conservation is the optimum sustained use of natural resources; therefore, cave conservation must provide not only for the protection of the character, decoration and biota of caves, but also for the means whereby people might enjoy and understand the caves that are their heritage. A cave is a natural subterranean cavity into which a man can enter to a point where daylight cannot be seen. Caves are not only interesting physical entities that provide distinctive sensory and perceptual experiences and invoke a variety of responses, but they also provide unique opportunities for scientific study. Speleology is the study of caves, and in New Zealand it attracts workers from many disciplines of the universities and government research establishments.(omitted)

• The Journal of Engineering Geology
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• v.31 no.3
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• pp.367-380
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• 2021

This study evaluated the stability through a three-dimensional numerical analysis method when a natural cave exists under a road in operation in Jeju Island. In order to confirm the geometric and geotechnical characteristics of the Jeju natural cave passing under the road, existing geotechnical survey reports were collected, and were studied the characteristics. In order to evaluate the effect of vehicle vibration loading on the natural cave in Jeju, three-dimensional numerical analysis was performed considering discontinuities. Through this, the stability of roads and caves with respect to vehicle speed and the depth of cover (distance from the road to the top of the natural cave) was evaluated and countermeasures were suggested. In order to secure the long-term stability of the Jeju natural cave that penetrates the lower part of the road, it was evaluated that systematic management such as long-term measurement management, reinforcement measures, and emergency measures would be necessary depending on the depth of the cover.

• Journal of the speleological society of Korea
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• no.4
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• pp.3-9
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• 1996

Ondal cave is located in Ha-ri Yongchun - myon, Tanyang - gun, Chungchongbuk - do, which has its site at the valley of southern side of Namhangang which winds up to the southwest. Namsan is kurungbong which is at the mid - slope of the steep and high mountain, Songsan which is 427 m high above sea level, and shows the aspect of the limestone area, a rough and steep mountain one.(omitted)

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.12-27
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• 2004

Studies on the Korean cave fauna were reviewed during the last seven decades since the first record of Antrokorean gracilipes Verhoeff, 1938. The cave animals have been reported by only 112 papers, 16 repoyts and ten books. In the results, a total of 257 species is recorded representing four phyla, ten classes, 31 orders, and 94 families, and also the holotype localities of 87 species are recorded from 36 caves and four wells in Boron. Arthropods are predominant consisting of 241 species (93.8％), and true spiders (Araneae) are a most diverse group with 97 species (37.7％) including 21 Korean endemic species belonging to 29 families.

• The Korean Journal of Quaternary Research
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• v.4 no.1
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• pp.1-13
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• 1990

The first well-preserved an immature fossil skeleton of Pleistocene age in South Korea was found at the quarry of Hungsu cave which consists of the Turubong Cave Complex, Ch'ongwon, Korea. This fossil remain has been designated as "Hungsu Cave Child". Associated with the individual were a small number of stone artifacts. While a precise date for this site is not available yet, the presence of fauna would suggest a warm period of an Upper Pleistocene date. Metric and non-metric methods are used for the description of the Hungsu child's skeleton. This fossil has been assigned a developmental age of 5 years, but can be considered to be the range of 4 to 6 years. Estimated cranial capacity ranged from 1,260 to 1,300 CC and the estimated stature from 110 to 120cm. The Hungsu child is differentiated by the superiority in size of skull, cranial length and height, and, most significantly, its greater parietal arc. On the basis of comparison of the total cranical characteristics of Hungsu child and other samples including hominid fossils and modern man of East Asia, it is assumed that Hungsu child can currently, be classified as "an anatomically modern man or anatomically Homo sapiens". Homo sapiens".uot;.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.757-761
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• 1996

The animal bone-remains excavated with earthwares at Cheju Kimnyungri cave site were investigated morphologically and osteometrically. The number of bone remains were 1706 pieces by morphological criteria. Based on the classification of bony pieces excavated in the cave site, the important animal species in Cheju island during the early Tamra period (presumably between A.D.0 - A.D. 500) was as follows; wild boar(75%), deer(17%), cattle(6%), and horse in small percentage. The excavated bone remains imply that the major fauna of animal species are composed of three species, including Sus scrofa, Cervus nippon and Bos taurus. These data suggests that the archaeological remains such as bone pieces are good indicators of the fauna animals, and of zoological entity in the island.

• International Journal of Highway Engineering
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• v.19 no.5
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• pp.59-68
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• 2017

PURPOSES : The objective of this study is to evaluate the potential risk level of road cave-ins due to subsurface cavities based on the deflection basin measured with falling weight deflectometer (FWD) tests. METHODS: Ground penetrating radar (GPR) tests were conducted to detect road cavities. Then FWD tests were conducted on 13 pavement test sections with and without a cavity. FWD deflections and a deflection ratio was used to evaluate the effect of geometry of the cavity and pavement for road cave-in potentials. RESULTS : FWD deflection of cavity sections measured at 60 cm or a closer offset distance to a loading center were 50% greater than more robust sections. The average deflection ratio of the cavity sections to robust sections were 1.78 for high risk level cavities, 1.51 for medium risk level cavities, and 1.16 for low risk level cavities. The relative remaining service life of pavement with a cavity evaluated with an surface curvature index (SCI) was 8.1% for the high level, 21.8% for the medium level, and 89.8% compared to pavement without a cavity. CONCLUSIONS : FWD tests can be applied to detect a subsurface cavity by comparing FWD deflections with and without a cavity measured at 60 cm or a closer offset distance to loading center. In addition, the relative remaining service life of cavity sections based on the SCI can used to evaluate road cave-in potentials.

• Journal of the Korean Geotechnical Society
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• v.33 no.12
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• pp.93-105
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• 2017

This study presents direct shear tests, model tests, and numerical simulations to assess the effect of reduction of soil strength because of saturation during formation of ground cave-in caused by damaged sewer pipe lines. The direct shear test results show that the saturation affects the cohesion of soil significantly although it does not influence the friction angle of soil. To experimentally reproduce ground cave-in, the model tests were performed. As ground cave-ins were accompanied with extreme deformation, conventional finite element method has difficulty in simulating them. The present study relies on generalized interpolation material point method, which is one of meshless methods. Although there are differences between the model test and numerical simulation caused by boundary conditions, incomplete saturation, and exclusion of groundwater flow, similar ground deformation characteristics are observed both in the model test and numerical simulation.