• Economic and Environmental Geology
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• v.50 no.6
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• pp.477-486
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• 2017

In this study, we analyze precise seabed geomorphology and conditions for comparing the nearshore areas of the Dongdo(East Island) and the Seodo(West Island) using detailed bathymetry data and seafloor backscattering images, in Dokdo, the East Sea. We have been obtained the detailed bathymetry data and the seafloor backscattering data. The survey range is about $250m{\times}250m$ including land of islets to the nearshore areas of the southern part of the Dongdo and the Seodo. As a result of bathymetry survey, the southern area of the Dongdo(~50 m) is deeper than the Seodo(~30 m) in the water depth. The survey areas are consist of extended bedrocks from land of the Dongdo and the Seodo. The underwater rock region of the Seodo is larger than the Dongdo. In spite of similar extended rocks features from islets, there are some distinctive seabed characteristics between the southern nearshore areas of the Dongdo and the Seodo. The Talus-shaped seafloor environment formed by gravel and underwater rocks originating from the land of the Dongdo is up to about 15 m depth. And the boundary line of between extended bedrocks and seabottom is unclear in the southern nearshore of the Dongdo. On the other hand, the southern coast of the Seodo is characterized by relatively large scale underwater rocks and evenly distributed sediments, which clearly distinguish the boundary of between extended bedrocks and seafloor. This is because the tuff layers exposed to the coastal cliffs of the Dongdo are weak against weathering and erosion. It is considered that there are more influences of the clastic sediments carried from the land of the Dongdo compared with the Seodo. Particularly, the land of the Dongdo has been undergoing construction activities. And also a highly unstable ground such as faults, joints and cracks appears in the Dongdo. In previous study, there are dissimilar features of the massive tuff breccia formations of the Dongdo and the Seodo. These conditions are thought to have influenced the different seabed characteristics in the southern nearshore areas of the Dongdo and the Seodo.

• Economic and Environmental Geology
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• v.56 no.5
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• pp.589-601
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• 2023

We compare high-resolution seabed bathymetry data and seafloor backscattering data acquired, using multi-beam, between 2018 and 2021 to understand topographic changes in the coastal area of Dokdo. The study area, conducted within a 500 m × 500 m in the southern coast between the islands where Dongdo Port is located, has been greatly affected by human activities, waves and ocean currents. The depth variations exhibit between 5 - 70 m. Irregular underwater rocks are distributed in areas with a depth of 20 m or less and 30 - 40 m. As a whole, water depth ranges similar in the east-west direction and become flatter and deeper. The bathymetry contour in 2020 tends to move south as a whole compared to 2018 and 2019. The south moving of the contours in the survey area indicates that the water depth is shallower than before. Since the area where the change in the depth occurred is mainly formed of sedimentary layers, the change in the coast of Dokdo were mainly caused by the inflow of sediments, due to the influence of wind and waves caused by these typhoons (Maysak and Haishen) in 2020. In the Talus area, which developed on the shallow coast between Dongdo and Seodo, the bathymetry changed in 2020 due to erosion or sedimentation, compared to the bathymetry in 2019 and 2018. It is inferred that the changes in the seabed environment occur as the coastal area is directly affected by the typhoons. Due to the influence of the typhoons with strong southerly winds, there was a large amount of sediment inflow, and the overall tendency of the changes was to be deposited. The contours in 2021 appears to have shifted mainly northward, compared to 2020, meaning the area has eroded more than 2020. In 2020, sediments were mainly moved northward and deposited on the coast of Dokdo by the successive typhoons. On the contrary, the coast of Dokdo was eroded as these sediments moved south again in 2021. Dokdo has been largely affected by the north wind in winter, so sediments mainly move southward. But it is understood that sediments move northward when affected by strong typhoons. Such continuous coastal change monitoring and analysis results will be used as important data for longterm conservation policies in relation to topographical changes in Dokdo.

• Journal of Ginseng Research
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• v.4 no.2
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• pp.197-221
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• 1980

Habitat observation, cultural experience of old and present plantation, weather factors in relation to crop stand and water physiology of root and leaf were reviewed. According to habitat observation ginseng plants love water but plate wit talus well grow at drained place with high moisture content in air and soil while ginseng plants were not found in dry or wet place. According to cultivation experience ginseng plants require abundant water in nursery and main field but most old planters believe that ginseng plaints are draught-loving thus require little water. The experience that rain especially in summer i.e unfavorable might be due to mechanical damage of leaves arid leaf disease infection, or severe leaf fall which is caused by high air temperature and coinsided with rain. According to crop stand observation in relation to weather factors abunsant water increased each root weight but decreased total yield indicating tile increase of missing root rate. Rain in summer was unfavorable too. Though rain in June was favorable for high yield general experience that cloudy day and rain were unfavorable might be due to low light intensity under shade. Present leading planters also do loot consider the importance of water in main field. Water content is higher in top than in root and highest in central portion of root and in stem of top. For seedling the heavier the weight of root is tile higher the water content while it reveries from two years old. Water potential of intact root appeared to be -2.89 bar suggesting high sensitivity to water environment. Under water stress water content severly decreased only in leaf. Water content of leaf appeared to be 78% for optimum, below 72% for functional damage and 68% for perm anent wilting. Transpiration or curs Principally through stomata in lower side of leaf thus contribution of upper side transpiration decreased with the increase of intensity. Transpiration is greater in the leaves grown under high light intensity. Thus water content is lower with high light inte nsity under field condition indicating that light is probable cause of water stress in field. Transpiration reached maximum at 10K1ut The decrease of transpiration at higher temperature seems to be due to the decrease of stomata aperture caused by water stress. Severe decrease of photosynthesis under water stress seems to be principally due to functional damage which is not caused by high temperature and Partly due to poor CO2 supply. Water potential of leaf appeared to be -16.8 bar suggesting weakness in draught tolerance. Ginseng leaves absorb water under high humidity. Water free space of leaf disc is %mailer than that of soybean leaf and water uptake appears to be more than two steps.

• Korean Journal of Veterinary Research
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• v.28 no.1
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• pp.1-16
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• 1988

The anatomical structure of pelvic limb, of thirty-one adult Korean native goats (Body weight: 14~17kg) was observed after skeletal preparation, and the osteometry was performed in each bone. The results were as follows: 1. The pelvic limb of the Korean native goat was composed of the hip bone, femur, patella, tibia, fibula, tarsal bones, metatarsal bone, phalanges and sesamoid bones. 2. The hip bone consisted of the ilium, ischium and pubis which fused each other, The gluteal surface of the ilium was directed dorsolaterally. The tuber sacrale and tuber coxae were formed at the dorsal apex and ventrolateral part of the iliac wing, respectively. The lesser ischiatic notch was deeper than the greater one. The ischiatic tubercles were triangular form and consisted of the dorsal, lateral and caudal ischiatic tubercles. The left and right hip bone indexes were 67.08, 66.20, the acetabular indexes were 93.78 and 92.10 and the obturator foramen. indexes were 53.84 and 54.77, respectively. 3. In femur, both of the greater and lesser trochanter were well developed but the third trochanter was not observed. The left and right femur indexes were 26.55 and 26.14, head indexes were 81.66 and 81.49 and the trochlear-epicondyle indexes were 42.47 and 41.63, respectively. 4. The patella was observed as an isosceles triangle with base lying proximal and the cranial surface was more convex. 5. The tibial shaft was sigmoid form and the popliteal notch was deep. There was a large nutrient foramen at the cranial aspect of the cranial intercondylar area. The tibial indexes were 22.09 in left and 21.10 in right. 6. The proximal extremity of the fibula was fused with the lateral condyle of the tibia but the distal one was observed independently as the malleolar bone. 7. The tarsal bones were five in number; the talus, calcaneus, centroquartal tarsal bone, first tarsal bone, and second-third tarsal bone. 8. The metatarsal bone was composed of a large metatarsal bone. resulted from the fusion of the third and fourth metatarsal bones, The structure of metatarsal bone was similar to the metacarpal bone but longer about 7mm. 9. The phalanges and sesamoid bones were similar to these of the thoratic limb. 10. The ratios of the lengths among the hip bone, femur, tibia and metafarsal bone were 1.71 : 1.54 : 1.73 : 1.00 in left and 1.68 : 1.53 : 1.72 : 1.00 in right, respectively.

• Journal of the Korean association of regional geographers
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• v.11 no.1
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• pp.19-28
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• 2005

Although Dokdo, small and dependent islands of Ulleung County, can be considered critical in terms of both geo-politics and physical geography, it is clear that Korean geographers have been too silent tn study Dokdo. In the author's view, such tendency is partly due to difficulties in access to Dokdo. In this sense this study would be meaningful for inquiring into the regional geomorphology of Dokdo regardless of only three-day field work. The major findings of the study are as follows. Firstly, the geology of Dokdo is composed of 8 rock units. Secondly, in a slope analysis of Dokdo volcano using GIS tool, steep slopes over $26^{\circ}$ account for 79.1% of whole slopes and even free faces, defined as slopes over $40^{\circ}$, account for 65.4%. Thirdly, the main landforms of Dokdo constitute volcanic landform, coastal landform and the others, such as talus, dyke, tafoni and erosional hollow. Fourthly, it turns out that advanced landform classification map of Dokdo can be designed by taking an approach tn regional geomorphology. Finally, based on a detailed review of the latest geological literature, I argue that part of landforms of East Dokdo(dongdo) is closer tn an erosional hollow than a small crater.

• Journal of Korean Foot and Ankle Society
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• v.6 no.1
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• pp.66-72
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• 2002

Purpose: To evaluate the overall results and its major affecting factors(athlete/associated injury) of modified Brostrom procedure for chronic ankle lateral instability. Materials and Methods: Fifty-one patients (51 ankles) with chronic ankle lateral instability were sub-grouped athletes and non-athletes and again sub-grouped with associated injury and without associated injury. Associated injuries were osteochondral defect(6), peroneal tendon abnormality(10), os subfibularae(4), os subtibialae(4), anterior impingement(5) and loose body(2). The overall surgical results were evaluated and also see whether or not athletes and associated injury affect the result. Result: Of the 51 operations performed, there were 39 excellent, 8 good and 4 fair as a whole. Of the 24 athletes operated, there were 19 excellent, 3 good, and 2 fair. Among the 27 non-athletes, there were 20 excellent, 5 good and 2 fair results. The average time to ordinary life in the non-athlete group was 2.5 months and average time to sports activity in the athlete was 4.5 months postoperatively. Those who didn't have any associated injury had all excellent result, on the contrary, those who had associated injuries, 14 excellent, 8 good and 4 fair results. All the fair results were associated with osteochondral lesion of talus. Whether or not the patient is athlete does not affect the surgical results, but whether or not there were associated injuries does affect the surgical results. Conclusion: Modified Brostrom procedure for chronic ankle lateral instability itself is an excellent to good operation. This procedure can be used in athletic populations who need high demand of sports activity. But chronic ankle lateral instability with associated injury group showed variable, less satisfactory results than those without associated injury. Careful preoperative and intraoperative examination should be done to find out the associated injury with chronic ankle lateral instability.

• Journal of Korean Foot and Ankle Society
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• v.17 no.2
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• pp.106-114
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• 2013

Purpose: Posteroanterior screw fixation is biomechanically stronger than anteroposterior screw fixation. However, there are few literature about the correlation between clinical results and more strength by posteroanterior fixation. This study was performed to evaluate the clinical outcomes of the accelerated rehabilitation following anterior open reduction and posterior percutaneous screw fixation for displaced talar neck fractures. Materials and Methods: Eighteen cases were followed up for more than 1 year after posteroanterior fixation using headless compression screw for talar neck fractures. The clinical evaluation was performed according to American Orthopaedic Foot and Ankle Society (AOFAS) score and Hawkins criteria. As radiographic evaluation, the degree of fracture displacement, period to union, and occurrence rate of complications such as avascular necrosis through MRI were measured. Results: The AOFAS score was average 90.4 points at the last follow-up. There were 7 excellent, 9 good, and 2 fair results according to the Hawkins criteria. Therefore, 16 cases(88.8%) achieved satisfactory results. The degree of fracture displacement had improved significantly from preoperative average 5.6 mm to 1.2 mm immediate postoperatively, and maintained to 1.1mm at the last follow-up. All cases achieved bone union, and the period to union was average 12.4 weeks. There were 3 cases of avascular necrosis of talar body and 2 cases of post-traumatic arthritis. Conclusion: Anterior open reduction and posterior percutaneous headless screw fixation seems to be an effective surgical method for displaced talar neck fractures, because of the possibility of accurate restoration of articular surface, fixation strength enough to early rehabilitation, and needlessness of hardware removal.

• Journal of Korean Society of Forest Science
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• v.109 no.1
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• pp.62-71
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• 2020

With the aim of restoring slow-moving landslide areas, this study collected fundamental data from tree-ring analysis of curved trees in these areas. We collected both upper and lower stem disks to measure the azimuth angles of six trees with growth curvature caused by tension cracks. Additionally, we analyzed various factors in the slow moving landslide area. The geological strata and main constitutive rocks in the study area were anorthosite-formed in the Precambrian period; moreover, there were no intrusive rocks, other geological strata, geological folds, or faults. The talus with weathered rocks was distributed in the upper zone of the slow-moving landslide area. According to annual-ring analysis of curved trees and terrain analysis by satellite imagery, slow-moving landslide occurred from the top to the bottom end of the slope between 1999 and 2011. There was a significant relationship (P < 0.01) between the azimuth angle of cracks caused by the slow-moving landslide and the angle of the curved trees. These results suggest that the occurrence of slow-moving landslides could be confirmed through analysis of annual-rings of curved trees, underground water levels, and terrain (by satellite imagery).

• Journal of The Geomorphological Association of Korea
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• v.18 no.3
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• pp.65-81
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• 2011

The landforms based on granite and basalt in Gosung, Gangwon province were analysed. Some part of this area experienced volcanic activities while most of the area was experiencing erosion of weathered mantle(saprolites) of mesoic granites during cenozoic period. Two different lithologies affect the mode of landscape evolution. The basalt covers the mountain tops as a 'cap rock' with flat surfaces. It shows relatively fresh rock surface with cliff or steep slops at the boundary with weathered granite. The blocks detached from the cliff accumulated at the foot of the cliff(talus) or moved and filled the valley(block streams). These debris slopes cover the deeply weathered granites. In the case of Oeum Mt. and Duibaekjae, the number of point of origin of the basalt flow is not clear. The orientation of blocks from block stream coincides with slope aspects and it can be assumed that the bolcks were moved by solifluction. The landscape change of the block streams are dominated by removal of weathered material from beneath of the valley rather than removal of bedrock blocks themselves.

• Journal of Korean Foot and Ankle Society
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• v.27 no.4
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• pp.131-136
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• 2023

Purpose: This study compared the clinical and radiology results of arthrodesis between the anterior and transfibular approaches with a lateral malleolar-saving procedure in ankle arthritis. Materials and Methods: This study was a retrospective study of 31 cases who underwent ankle arthrodesis with the anterior approach (14 cases) and trans-fibular approach (17 cases). The remnant lateral malleolus was fixed during the trans-fibular procedure. The patients included 17 females and 14 males with a mean age of 57.2 (range 41~73) years; the mean follow-up was 30.4 (range 15~68) months. The clinical and radiology outcomes, including the American Orthopedic Foot & Ankle Society (AOFAS) scores, visual analog scale (VAS), and union time, were recorded. The complications and subjective satisfaction degrees were also recorded and compared between the two groups. Results: Clinically, the preoperative mean AOFAS score and VAS in the anterior approach group were 39.3 and 7.4, respectively, which changed to 61.9 and 3.1 postoperatively. In the trans-fibular approach group, the mean AOFAS score and VAS increased from 36.6 to 64.2 and 7.1 to 2.4, respectively. On the other hand, no significant differences in the clinical results were observed between the two groups. The time to achieve union was 9.2 and 11.6 weeks in the anterior and transfibular approach groups, respectively. Three patients (21%) complained of tenderness and discomfort around the fibular tip in the anterior approach group, and seven patients (41%) showed a gap between the talus and remnant lateral malleolus in the trans-fibular approach group. Conclusion: There was no difference in the clinical and radiological results between the anterior and transfibular approaches with a lateral malleolar saving procedure in ankle arthrodesis. Careful selection of the approach method according to the patient's preoperative condition is needed to prevent remnant discomfort or nonunion around the lateral malleolus.