• Economic and Environmental Geology
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• v.3 no.3
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• pp.169-176
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• 1970

Kubong Gold Mine is located in Kuryongri, Sayang-myun, Chungyang-gun, Choongchung-Namdo.(latitude $36^{\circ}24^{\prime}N$. longitude $126^{\circ}45^{\prime}30^{{\prime}{\prime}}E$) The mine was begun to work soon after the inhabitants of this village had accidently discovered the outcrops in April 1908. It is one of the largest gold mines in Korea which produces 4,500 tons of crude ore a month. The geology in the area consists of granitic gneiss, banded gneiss, augen-gneiss, mica schist, limesilicate of Pre-Cambrian series and sedimentary rocks(sandstones & conglomerates) of Daedong series. Basic dikes intrude the former formations. The country rock of the ore deposit is a group of the metamorphic rocks mentioned above. Gold-silver bearing quartz vein contains small amounts of pyrite, chalcopyrite, arsenopyrite, galena and sphalerite in which gold and silver occur as native state. The vein strikes $N30^{\circ}{\sim}60^{\circ}E$ and dips $20^{\circ}{\sim}50^{\circ}S$ and the average width of the vein is estimated 1 to 1.5m. Average grade of ore is Au:6~8gr/t and Ag:5~6gr/t. The ore shoot continues from the outcrop to the depth of -1760ML with dip of $20{\sim}25^{\circ}$ and strike extension reaches to 400m at the depth of -1440 ML and to more or less 200m at below. Highgrade of ore vein was found at the lowest level of the ore shoot at the time of recent field survey at the end of August 1970. Its average grade was estimated as Au:20gr/t and its width 1~2.5M in average. A series of futher prospecting for other new ore shoot or parallel veins are urgent and crosscut prospecting along the horizontal level is strongly recommended.

• Journal of fish pathology
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• v.24 no.3
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• pp.213-223
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• 2011

Among wild marbled sole, Pleuronectes yokohamae caught in west coastal area, Chungnam, tumor-bearing fish were found. Parasites and pathogenic bacteria were not detected and CPE was not observed. Using the light microscope, the epidermal layer of wild P. yokohamae was significantly thickened compared to the normal skin. The lesion was formed papillary folds. Hypertropical epithelial cells revealed karyolysis, marked nucleolus and cloud swelled cytoplasm. In the epidermal layer of the lesion, X-cell that is characterized by oval and small pale nucleus and prominent nucleolus was observed. Dermal layer had newly formed vessels. The size of mucous cell in the papilloma lesion was significantly increased compared to the normal. In this study, no pathogens were found, so future works for finding cause of the papilloma in the P. yokohamae are needed.

• Tunnel and Underground Space
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• v.18 no.6
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• pp.427-435
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• 2008

In this paper, review was made for the excavation method and optimum bench length for unstable tunnel face in case of rock classification type V in order to make the best use of in-situ bearing capacity. 3D FEM analyses were performed to investigate the influences on the tunnel face and adjacent area with regard to the pattern and number of bolts when face bolts were used as a supplementary measure. As a result of this study, full section excavation method with sub-bench is effective in reducing the displacement greatly due to early section closure. Displacement-resistant effects in accordance with the bolting patterns are grid type, zig-zag type and then circular type in order of their effect. And horizontal extrusion displacement of tunnel face reduces as the number of bolts increase. A grid type face bolt covering $1.5m^2$ of tunnel face could secure the face stability in case of full section excavation method with sub-bench.

• Journal of the Mineralogical Society of Korea
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• v.10 no.2
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• pp.148-161
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• 1997

Based on the X-ray powder diffraction (XRD) and M ssbauer spectroscopy, the thermal behavior and phase transformations of two clays are investigated for raw and fired conditions, which are collected from Kwangryeongli and Ildo district in Cheju Island. M ssbauer spectra at room temperature and 20for two clays show that paramagnetic Fe3- is the structural iron of the layer silicate and ferrihydrite, and superparamagnetic goethite has about 50% of total iron contents. The XRD peaks of hematite for the fired clays appear from 80$0^{\circ}C$ in Kwangryeongli clay and from $600^{\circ}C$ in Ildo district clay, respectively. The structural Fe2+ was completely oxidized into Fe3- at 40$0^{\circ}C$ for Kwangryeongli clay and 50$0^{\circ}C$~$600^{\circ}C$ for Ildo district clay, respectively. The structural Fe2+ was completely oxidized into Fe3- at 40$0^{\circ}C$. For the temperature ranging from 40$0^{\circ}C$ to $700^{\circ}C$~80$0^{\circ}C$, two fired clays exhibit the dehydroxylation of the clay mineral. A disintegration of the clay mineral structure is observed from $700^{\circ}C$~80$0^{\circ}C$ to 110$0^{\circ}C$, followed by the onset and spread of vitrification process. It is also shown that well-crystallized hematite phase is formed at the temperature higher than 110$0^{\circ}C$ and the relative absorption area decreases, which might be related to the recrystallization of alluminosilicate matrix.

• Journal of Society of Preventive Korean Medicine
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• v.6 no.1
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• pp.36-50
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• 2002

Health industry, a knowledge based high value-added industry, is being considered as a strategic area for the 21C and many advanced countries are making every endeavors for the promotion of health industry along with information technology, new materials, and mechatronics. Korean health industry, however, has been excluded from the governmental supports as well as bound by strict regulation so far, and there is a significant gap in technology compared with advanced countries. In 21C, technology is the main factor of national competitiveness and that is why the role of R&D institutes are so important in the high level of competition to cope with the technology protection policies of advanced countries. In this article, with Directory of Korean R&D Institutes published by Korea Industry Technology Association, I reviewed the trends of R&D institute of health industry. Main findings of the research can be summarized as follows. The portion of health industry R&D institute is 3.6% of total R&D institute but the amount of R&D investment is over than 5% This means health industry are knowledge based and R&D intensified industry, meanwhile the variations of same industry R&D institutes of health industry is huge in R&D investments and other activities. Regional distributions of health industry institutes show some kind of different patterns in each industry areas. Medical devices and Medical informatics's preference of metropolitan region are distinguished with other industry areas. Many of the institutes are located in same site of it's company rather than operating separate building for R&D specific uses. It is better for transforming ideas to products and close cooperation of research body with product lines, but it is a handicap for networking and communicating with other research institutions too. It takes 18.4yrs for bearing R&D institute on the average. For a long times 'copy products' or 'me too products' policies were easy way to maintain business entities. But recently, it is recognized that research activities are essential component of sustaining it's own business firms. This means technology itself is leading power of corporation itself in the high level of competition.

• Journal of Korean Society of Steel Construction
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• v.29 no.2
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• pp.169-180
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• 2017

Cyclic loading tests for beam-to-column weak-axis connections were performed to investigate the seismic performance. In this study, the connections were developed to improve the constructability on the basis of investigation for existing small-size steel structures. The primary test parameter is the number of high-tension bolts which are used to connect steel beam and column using exterior and interior flange plates. Test results showed that the number of bolts had a significant effect on the cyclic behavior of beam-column weak-axis connections. From the analysis of test results, it is concluded that more than four bolts in the connections can satisfy the requirements of semi-rigid connection presented in current design codes. All of specimens showed the bearing failure around bolt holes and fracture at the beam flange. However, when the web height and the flange width is relatively small, the number of the bolts used in the connections might be limited. Thus, the additional research in this area is needed.

• Archives of Plastic Surgery
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• v.32 no.4
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• pp.539-542
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• 2005

Reconstructions of soft tissue defect of the posterior ankle including Achilles the tendon should take into account not only coverage but functional outcome. Various methods of tendon transfer and tendon graft have been reported as a single-stage procedure. With advances and refinements in microsurgical techniques, several free composite flaps including tendon, fascia, or nerve have been used in single-stage reconstructions of large defects in this area minimizing further damage to the traumatized leg. However, when free flap is not feasible for some reasons, this cannot be accomplished successfully. Here we present a patient with Achilles tendon and circumferential large soft tissue defect. Because of circulatory compromise of the lower extremity, free flap reconstruction could not be applied. Instead, cross-leg composite flap of the dorsalis pedis flap including the extensor hallucis brevis musle and tendon, and tendon strips of the Second, third and fourth extensor digitorum logus were employed, Functional reconstruction of the tendon and resurfacing were obtained at the same time. The flap was detached 3 weeks postoperatively, and the transplanted flap has survived without any complications. By 3 months after surgery, full weight bearing, tip-toe standing and even walking without crutch assistance was possible. When functional reconstruction with the free flap is unattainable in the large defect of the posterior ankle including the Achilles tendon, cross-leg composite island flap of dorsalis pedis flap and tendon strips of the extensor digitorum longus tendon is a viable alternative.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.569-573
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• 2008

Purpose: Surgical excision of the subcutaneous tissues, with or without skin excision in the axillary hair-bearing area, has been the treatment of choice in treating osmidrosis for several decades. However, long periods of postoperative immobilization of a shoulder joint, partial necrosis of skin flaps or the possibility of hematoma and scars have occurred frequently. So we used $XPS^{(R)}$ microresector(Shaver) in procedure which requires removal of soft tissue for comparing results between surgical excision and the laters. Methods: From January 2007 to February 2008, a total of 20 patients(8 male and 12 female) underwent $XPS^{(R)}$ microresector(Shaver) assisted aspiration for treating osmidrosis. The mean age of the subjects was 21.9, and we tried to analyze some advantages of $XPS^{(R)}$ microresector(Shaver). Results: The average operation time was 61.6 minutes. This results can show that the patients who received $XPS^{(R)}$ microresector(Shaver) assisted aspiration can accomplish better outcomes than any other procedures in terms of operation time at least. Moreover, no significant postoperative complications occurred in our studies. Subjects have been followed up from 2 months to 1 year and among these patients, no one suffered from critical complications. Conclusion: In brief, $XPS^{(R)}$ microresector(Shaver) is able to shorten the time of operation and simplify the procedures relatively and this device has more superiorities in wound healing by maintaining of vascularized dermal skin flaps. It means that $XPS^{(R)}$ microresector (Shaver) can prevent flap necrosis, axillary hair loss and minimalize scarring and bleeding. Thus, we expect that these advantages can lead to better patient's comfort and self-confidence than several previous procedures.

• Economic and Environmental Geology
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• v.32 no.3
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• pp.293-306
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• 1999

The lower Permian jungseong Formation, Taebaegsan basin (Baegunsan Syncline), represents a coal-bearing siliciclastic succession which was later modified by the Songrim or Dabo orogeny. Sandstone perography and clay mineralogy were studied to understand the thermal history of the Jangseong Formation during basin evolution. Petrographic study indicates the Jangseong sandstones are composed of quartz, feldspar, lithic fragments (metamorphic and sedimetary), and varying proportions of matrix and cement. The dominance of quartz(<97%) over feldspar (<1%) and lithic fragments (<2%) classifies most Jangseong sandstones as quartz arenotes or quartzwackes, but lithic graywackes and sublithic arenite locally occur. The diagentic features of these sandstones include mechanical compaction, cemenation by quartz and clay minerals indentified in the Jangseong Formation by X-ray diffraction analysis are late-stage clay pore-filling. Clay minerals isdentified in the Jangseong Formation by X-ray diffaction analysis are illite, kaolinte, and pyrophyllite with a minor amount of chlorite and micas. The illite, kaolinite, and pyrophyllite appear to be largely autjigenic based on their well-crystallinity forms. There authigenic clay minerals form clay minerals form clay coats/rims and late-stage pore-filling cements, Illitecrystallinity shows that the Jangseong formation has been in late-diagenetic zone to early-epizone, which ranges in temperature from $200^{\circ}C$ to $300^{\circ}C$. In assition, kaolinite-pyrophyllite transition suggests that paleotemperature of the formation has reached at least $265^{\circ}C$. Such temperatureis likely to be consistent with homogenixation temperatures of fluid inclusions in quartz veins in the formation. Thus, the Jangseong Formation has been subjected to paleotemperature of about $265^{\circ}C$. The major heat source responsible for paleotemperature may be hydrothermal solutions. The passage of hydrothermal solutions was probably assisted by fractures created during the basin-modifying tectonism of the taebaegsan basin.

• Journal of Korean Tunnelling and Underground Space Association
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• v.7 no.2
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• pp.97-108
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• 2005

This paper presents the effect of tunneling and groundwater interaction on tunnel behavior. As part of this study, design issuses for tunneling situations similar to that considered in this study are first identified. A parametric study is then conducted on tunneling situations frequently encountered in Seoul area using a 3D stress-pore presure coupled finite-element model with emphasis on the effects of ground and lining permeabilities. The results indicate that tunneling in water bearing ground results in a deeper and wider settlement trough, increased axial thrusts in shotcrete lining than those without the groundwater. Also revealed is that the axial thrusts in shotcrete lining are governed by the relative permeability between the ground and the lining. Design implications of the findings from this study are discussed.