• The Journal of the Petrological Society of Korea
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• v.17 no.1
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• pp.1-15
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• 2008

The metasedimentary rocks of the Nampo Croup consisting of metaconglomerates, metasandstones, phyllites are exposed in the area of the Daechcon beach and Maryangri, Seocheon-gun. Their typical metamorphic assemblages of Bt-Mus-Grt-Qtz (${\pm}Pl{\pm}Chl$) and Bt-Mus-Qtz (${\pm}Pl{\pm}Chl$) indicate that they have been under intermediate P/T type metamorphism and were metamorphosed to garnet zone grade of amphibolite-facies during the Daebo Orogeny. Pressure-temperature conditions of peak metamorphism estimated from geothermobarometries are $560{\sim}595^{\circ}C$, $6.9{\sim}8.2\;kb$ respectively. The results of K-Ar biotite age determination are $143.2{\pm}3.6\;Ma$, $122.6{\pm}2.4\;Ma$ and $124.8{\pm}2.4\;Ma$ and the last two ages are considered as the results of later-stage thermal perturbation. On the bases of the formation age of Daedong Supergroup of $187{\sim}172\;Ma$ (Han et al., 2006; Jeon et al., 2007) combined with the results of this study, the hypothetical model of tectonometamorphic evolution of the study area during Daebo Orogeny is proposed. Crustal thickening resulted from folding and duplexing of thrusts in the area initiated at around 175 Ma just after sedimentation of Nampo Croup. And then rapid cooling by normal faulting due to crustal extention followed immediately after the peak metamorphism to the closure temperature of biotite.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.2
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• pp.70-77
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• 2012

The Ladle Furnace Slag, about 20% of the electric arc furnace slag, has high content of free CaO and free MgO, which generates the expansion collapse by hydration reaction. Although many researchers have been endeavoring to recycle the EAF reducing slag in construction fields, there is not found the effective recycling method up to now. However, the LFS(Ladle Furnace Slag) contains mineral composition of the system of calcium aluminate with high-reactivity. Therefore, it is possible to developed the quick setting property and the high strength at the early age by the rapid cooling. This study aimed to check the reactive minerals and predict the reactivity with water on the LFS discharged from different steel product plants. The test results show that many types of LFS has hydration reactivity and can use in construction field as a inorganic binder with the rapid setting property.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.5 no.3
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• pp.291-299
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• 2015

With recent surge of attention to heating and air conditioning energy consumption, the need for evaluating performance of heating and air conditioning energy is also on the rise. This research aims to propose daily-life based evaluation method as an alternative to existing one, as well as to apply the method in real life to prove its validity. The results are as following. 1) I studied temperatures preferred by persons indoors and appropriate level of temperature, and the results show that properties of such persons such as age is directly linked with pleasantness of the room, but the issue lies with the fact that such properties are not considered in existing performance evaluation of heating and air conditioning. 2) Daily life based evaluation proposed herein reflects such properties of persons indoors. It controls heating / air conditioning devices installed in the test bed with the same size as a real life room to get quantitative and visual performances in our daily life as well as simple temperature information. 3) To verify validity of daily life based evaluation, I conducted different evaluation sessions with and without a blind and also based on ages of persons indoors. Results based on properties of persons showed difference of 77.6%, leading to effective analysis of energy consumption pattern by heating / air conditioning devices. This research takes significance in that it comes with a new performance evaluation method based on real life, and I gather that further studies are required to develop more multilateral performance evaluation in order to verify and improve technology for reduction of energy consumption.

• Economic and Environmental Geology
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• v.9 no.2
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• pp.85-106
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• 1976

The Bulgugsa acidic igneous rocks of the late Cretaceous age are largely distributed in Busan area, which is located in the southeastern corner of the Korean Peninsula. These igneous rocks comprise in ascending order, felsite, dacitic-rhyolitic welded tuffs, granite porphyry and granitic rocks. The former three members represent the early phase of volcanic activities, so that they are named as Jangsan volcanic rocks. The granitic rocks consist of granodiorite, hornblende biotite granite, Kumjongsan granite, fine grained granite, and Daebyen granite, represent the late phase of igneous activities. The Kumjongsan grainte, the largest pluton of the granitic mass, emplaced between two great vertical faults trending NNE. New chemical analyses of 33 rock samples of these acidic rocks are given. Their chemical compositions are generally similar to those of the late Mesozoic acidic igneous rocks of the northern Ashio mountains, and C-Zone granite group of the Ogcheon geosyncline, with their characteristic variation trends of several oxides. Their chemical compositions also show that $Al_2O_3$ is high value, and differentiation index is high, too. Systematically developing joints in Kumjungsan granite are divisible into two types at least. One is the NS-N $20^{\circ}E$ trendirig, $85^{\circ}{\sim}90^{\circ}$ dipping type of joint system which coincides with the trends of distribution of the granite mass and the dikes intruding this granite. Joints of this type may be cooling joints generated as tension cracks. The other is the $N60^{\circ}{\sim}70^{\circ}W$ or $N40^{\circ}{\sim}60^{\circ}E$ trending type of joint systems. It is considered that. joints belonging to this type may be shear joint occurring under the state of south-north tectonic couple acting at the east and west side of the granite mass. Igneous activities of the the Bulgugsa acidic igneous rocks in Busan area was taken place as. follows, formation of the magma reservoir, eruption and intrusion of felsite, consolidation of vents. and increasing vapor pressure in magma reservoir, eruption of pyroclastic flows, caldera collapse, intrusion of granite porphyry, and intrusion of granitic rocks at the latest stage.

• Economic and Environmental Geology
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• v.28 no.6
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• pp.541-551
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• 1995

The Yeongdeog gold-silver deposits at Jipum, Gyeongsangbugdo, is of a middle Paleogene $(45.52{\pm}1.02Ma)$ vein type, and is hosted in shale and sandstone of Cretaceous age. Based on mineral paragenesis, vein structure and mineral assemblages, the ore mineralization can be divided into two distinct depositional stages. The early stage is associated with base-metals such as pyrite, arsenopyrite (27.99~30.99 at%), hematite, rutile, pyrrhotite, sphalerite (10.53~18.42 FeS mole%), chalcopyrite and galena with wallrock alteration such as chlorite, sericite and pyrite. The late stage is characterized by the Au-Ag mineralization such as electrum, Ag-bearing tetrahedrite, freibergite, pyrargyrite, unidentified mineral, pyrite, sphalerite (1.08~5.57 FeS mole%), chalcopyrite and galena. Fluid inclusion data indicate that fluid temperatures and salinities range from 343 to $227^{\circ}C$ and from 8.3 to 5.7 wt% eq. NaCl in early stage, respectively. Temperatures and salinities of NaCl eq. wt% range from 299 to $225^{\circ}C$ and from 12.9 to 4.3 in late stage, respectively. They suggest that complex cooling histories were occured by the mixing of the fluids. Sulfur fugacity $(-logfs_2)$ deduced by mineral assemblages and composition ranges from 8.3 to 14.7 atm. in early stage, and from 8.8 to 14.5 atm. in late stage. It suggests that the mineralization was related to decrease of temperature in early stage and fluctuations of $fS_2$ with decrease of temperature in late stage. Sulfur and oxygen isotope compositions are 4.48~5.60‰ and 9.25~10.8% in early stage, and late stage is 4.84~7.00‰ and 5.7‰, respectively. It indicated that hydrothermal fluids may be magmatic origin with some degree of mixing of another water during paragenetic time.

• Publications of The Korean Astronomical Society
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• v.27 no.4
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• pp.243-248
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• 2012

Nearby spiral galaxies M101 and M81 are considered to have undergone a galaxy-galaxy interaction. M101 has experienced HI gas infall due to the interaction. With AKARI far-infrared (IR) photometric observations, we found regions with enhanced star forming activity, which are spatially close to regions affected by the interaction. In addition, the relation between the star formation rate (SFR) and the gas content for such regions shows a significant difference from typical spiral arm regions. We discuss possible explanations for star formation processes on a kiloparsec scale and the association with interaction-triggered star formation. We also observed the compact group of galaxies Stephan's Quintet (SQ) with the AKARI Far-infrared Surveyor (FIS). The SQ shows diffuse intergalactic medium (IGM) due to multiple collisions between the member galaxies and the IGM. The intruder galaxy NGC 7318b is currently colliding with the IGM and causes a large-scale shock. The 160 micron image clearly shows the structure along the shock ridge as seen in warm molecular hydrogen line emission and X-ray emission. The far-IR emission from the shocked region comes from the luminous [CII]$158{\mu}m$ line and cold dust (~ 20 K) that coexist with molecular hydrogen gas. Survival of dust grains is indispensable to form molecular hydrogen gas within the collision age (~ 5 Myr). At the stage of the dusty IGM environment, [CII] and $H_2$ lines rather than X-ray emission are powerful cooling channels to release the collision energy.

• Ocean and Polar Research
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• v.37 no.1
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• pp.23-35
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• 2015

A 450 m-long sediment section was recovered from Hole U1359D located at the eastern levee of the Jussieau submarine channel on the Wilkes Land continental rise (East Antarctica) during IODP Expedition 318. The age model for Hole U1359D was established by paleomagnetic stratigraphy and biostratigraphy, and the ages of core-top and core-bottom were estimated to be about 5 Ma and 13 Ma, respectively. Biogenic opal content during this period varied between 3% and 60%. In the Southern Ocean, high biogenic opal content generally represents warm climate characterized by the increased light availability due to the decrease of sea-ice distribution. The surface water productivity change in terms of biogenic opal content at about 10.2 Ma in the Wilkes Land continental rise was related to the development of Northern Component Water. After about 10.2 Ma, more production of Northern Component Water in the North Atlantic caused to increase heat transport to the Southern Ocean, resulting in the enhanced diatom production. Miocene isotope events (Mi4~Mi7), which are intermittent cooling intervals during the Miocene, appeared to be correlated to the low biogenic opal contents, but further refinement was required for precise correlation. Biogenic opal content decreased abruptly during 6 Ma to 5.5 Ma, which most likely corresponds to the Messinian salinity crisis. Short-term variation of biogenic opal content was related to the extent of sea-ice distribution associated with the location of Antarctic Polar Front that was controlled by glacial-interglacial paleoclimate change, although more precise dating and correlation will be necessary. Diatom production in the Wilkes Land continental rise increased during the interglacial periods because of the reduced sea-ice distribution and the southward movement of Antarctic Polar Front.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.338-343
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• 2017

In this study, blast furnace slag powder was used in concrete to help reduce carbon dioxide emissions and to recycle industrial waste. Blast furnace slag powder is a byproduct of smelting pig iron and is obtained by rapidly cooling molten high-temperature blast furnace slag. The powder has been used as an admixture for cement and concrete because of its high reactivity. Using fine blast furnace slag powders in concrete can reduce hydration heat, suppress temperature increases, improve long-term strength, improve durability by increasing watertightness, and inhibit corrosion of reinforcing bars by limiting chloride ion penetration. However, it has not been used much due to its low compressive strength at an early age. Therefore, this study evaluates the effects of steam curing for increasing the initial strength development of concrete made using slag powder. The relationship between compressive strength, SEM observations, and XRD measurements was also investigated. The concrete made with 30% powder showed the best performance. The steam curing seems to affect the compressive strength by destroying the coating on the powder and by producing hydrates such as ettringite and Calcium-Silicate-Hydrate gel.

• Journal of Chest Surgery
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• v.25 no.5
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• pp.511-517
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• 1992

From January 1988 to December 1990, 18 adult patients with aortic disease underwent surgical repair using hypothermia and total circulatory arrest. The age at operation ranged from 17 years to 64 years[mean 45.2$\pm$10.7 years]. We disease entities included aortic dissection in 12, aortoannuloectasia in 3 and thoracic aortic aneurysm in 3 cases. Partial cardiopulmonary bypass via femoral vessels along with surface cooling was used upon the induction of deep hypothermia[18~20oC]. Modified Bentall operation was performed in 7 cases, ascending aorta replacement in 6, graft interposition in descending thoracic aorta in 3 and others in 2 cases. The circulatory arrest was maintained for periods of 2 minutes to 86 mimutes[mean 34.7$\pm$5.0 minutes]. Overall hospital mortality was 27.8%[5/18]: brain damage was responsible for the death of 2 patients. 4 patients out of 13 survivors experienced postoperative neurologic dysfunction, which was proved to be self-limited except one case showing left hemiparesis. 12 patients were followed up postoperatively with the mean follow-up period 22.7$\pm$10.1 months. There was no death. No new neurologic problems were observed during follow-up period. All but one patient showing recurrent dissection and aortic regurgitation are in exellent clinical condition. These clinical data suggests that the principle of deep hypothermia and total circulatory arrest can be applied rather safely in adult patients, especially in the treatment of patients with aortic disease, it can be a valuable adjunct with better clinical results.

• Journal of Life Science
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• v.17 no.12
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• pp.1739-1743
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• 2007

The purpose of this study was to develop a movement program adopted from Bellydance, and to analyze the effects of the Bellydance program on the blood Components and Deoxypyridinoline, Osteocalcin in middle aged women. The Bellydance program was composed of warming-up (10min), main exercise (40min) and cooling-down (10min) parts. The 40 middle-aged women between 40 and 60 year old were divided into two group; the control group (8 women), the Bellydance group (8 women). The Bellydance program was applied three times a 12weeks. The result of this study were as follow. RBC, Hb, WBC, PLT, Osteocalcin was measured in a whole blood. The belly dance group showed WBC was more significantly decreased than control group, but RBC, Hb, PLT were insignificant in other groups. The belly dance group showed Deoxypyridinoline was more significantly increased than control group, but Osteocalcin were insignificant in other groups. Therefore this program can be available in middle aged women.