• Resources Recycling
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• v.25 no.2
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• pp.60-68
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• 2016

In this study, earlier analyzed tetrapod, one of an original group of offshore constructions studied for manufacturability of the concrete using the properties of steel making slag aggregate. steel making slag aggregate assessment, RCS and Blast Furnace Slag : the 20 mm air-cooled slag and combinations by 50 %, aggregate properties on the most appropriate for the properties of recycled aggregate concrete optimal mix, and assessing it. Properties of concrete used to be derived are judged as to bury the studies show that the hollowing-out of the RCS, plastic sole use is in the workability of the aggregate, plastic in the 20 mm slag also assessed to be a slight disadvantage, but RCS by mixing air-cooled coarse and 50 percent to 20 percent 50 mm. Thus, steel making slag marine structures using recycled aggregate, in rapid chilled slag or air-cooled slag. The sole use of the aggregate them than to combine the aggregate of concrete. After they satisfy the quality standard quality shall be used will aggregate steel making slag who meet the criteria concrete manufacturing in general or par with the aggregate of concrete. Performance was assessed as to develop a more than that.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.12
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• pp.815-824
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• 2016

The fuel assembly for pressurized water reactor (PWR) consists of fuel rod bundle, spacer grid and bottom/top end fittings. The cooling water in high pressure and temperature is introduced in lower plenum of reactor core and directed to upper plenum through the subchannel which is formed between the fuel rods. The main thermal-hydraulic performance parameters for the PWR fuel are pressure drop and critical heat flux in normal operating condition, and quenching time in accident condition. The Korea Atomic Energy Research Institute (KAERI) has been developing an advanced PWR fuel, dual-cooled annular fuel and accident tolerant fuel for the enhancement of fuel performance and the localization. For the key thermal-hydraulic technology development of PWR fuel, the KAERI LWR fuel team has conducted the experiments for pressure drop, turbulent flow mixing and heat transfer, critical heat flux(CHF) and quenching. The computational fluid dynamics (CFD) analysis was also performed to predict flow and heat transfer in fuel assembly including the spent fuel assembly in dry cask for interim repository. In addition, the research cooperation with university and nuclear fuel company was also carried out to develop a basic thermal-hydraulic technology and the commercialization.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.3
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• pp.452-459
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• 2016

Nutritional compositions, volatile compounds, and sensory attributes of grilled and fast-chilled mackerel (Scomber japonicus) were analyzed in order to examine its practical utilization as a food resource compared to commercial frozen mackerel. In the proximate analysis, lipid contents were $27.3{\pm}2.7%$ in grilled and fast-chilled mackerel. Palmitic acid was the most predominant fatty acid (20.68% and 18.88%), and the percentages of polyunsaturated fatty acid were higher than 40% in both. No benzopyrene was found in the grilled mackerel, and even grilling was employed at $260^{\circ}C$. For chemical stabilities, para-anisidine value (8.56 vs. 9.26) and acid value (2.96 vs. 3.35) in grilled mackerel were improved compared to those of commercial mackerel. Moreover, color index of grilled mackerel, a physiological property, showed greater lightness than commercial mackerel. Lastly, analysis of volatile compounds by gas chromatographic analysis and sensory tests by trained panels demonstrated higher potential for grilled mackerel as a highly marketable product compared to commercial mackerel. Taken altogether, the above results provide important preliminary results for utilization of grilled and fast-chilled mackerel as a quality food.

• The Journal of the Petrological Society of Korea
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• v.16 no.2 s.48
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• pp.73-81
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• 2007

A basaltic tuff formation (Upper Basaltic Tuff of the Janggi Group) occurs in close association with basalt (Yeonil Basalt) at the Tertiary Janggi basin. The purpose of this paper is to describe the occurrence of the basaltic tuff and associated basalt and to determine their mode of formation. The basaltic rocks of the study area show few distinct lithofacies, all of which are originated from the interaction of basaltic magma with external water. The four lithofacies include (1) sideromelane shard hyaloclastite, (2) pillow breccia, (3) entablature-jointed basalt, and (4) in-situ breccia. The sideromelane shard hyaloclastite constitutes most of the Upper Basaltic Tuff and has a gradual contact with the pillow breccia. The pillow breccia consists of a poorly sorted mixture of isolated and broken pillows, and small basalt globules and fragments engulfed in a volcanic matrix of sideromelane shard hyaloclastite. The entablature-jointed basalt occurs as a small body within the hyaloclastite. It is characterized by irregularly-curved joints known as entablature. The in-situ breccia occurs as a marginal facies of entablature-jointed basalt, and its width varies from 10 to 30m. The result of this study indicates that the basaltic tuff and associated basalts of the study area were produced by the volcanic activity of same period and the basaltic tuff was formed by subaqueous eruption of basaltic lava followed by nonexplosive quench fragmentation.

• Resources Recycling
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• v.25 no.3
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• pp.20-28
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• 2016

Assessment on adequate dosage of superplasticizer in eco-friendly ultra-high performance concrete (UHPC) containing industrial by-products was carried out from the standpoint of workability. Various types of industrial by-products, including blast-furnace slag, coal bottom ash and rapid-cooled electric arc furnace oxidizing slag, were utilized, and the effects of dosage of superplasticizer on the workability and strength of UHPC containing the by-products were evaluated. By utilizing the by-products, the workability of UHPC was improved and required dosage of superplasticizer was reduced. In addition, the material cost for UHPC with by-products was decreased due to reduced dosage of superplasticizer.

• Applied Microscopy
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• v.21 no.2
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• pp.57-66
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• 1991

The main purpose of this paper was to investigate the change of rapidly solidified microstructures and dispersoid behavior according to heat-treatment in the Al-Fe-V-Si-(Mn) alloys. It was found that (111) preferred orientation identified by X-ray diffraction and fine subgrain/large grain were observed in the rapidly solidified Al-Fe-V-Si-(Mn) alloys. Cell boundary of the zone A was composed of the microcrystalline, whereas that of the zone B was amorphous. Decomposition of the Al-Fe-V-Si-(Mn) alloys occurred at about $300^{\circ}C$. These alloys exhibited excellent thermal stability at the elevated temperature. Microstructure of the zone B was more stable than that of the zone A. The spherical dispersoid and 5-fold symmetry phase was also more thermally stable than the amorphous structure of cell boundary.

• Journal of Energy Engineering
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• v.4 no.3
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• pp.379-386
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• 1995

0.5 T/D 용량의 슬러리를 이용한 분류층가스화기에서의 인도네시아 탄인 Roto탄을 이용한 가스화 실험을 통하여 개발된 가스화기의 성능과 석탄가스화 특성을 파악하였다. 200 mesh 이하로 분쇄된 미분탄을 62.5%(H2O/coal=0.6)로 물과 혼합된 슬러리를 0.5%의 유도화제와 화재의 20%의 CaO를 화재의 융점강하를 위하여 첨가시켰다. 화재의 융점이 1511$^{\circ}C$에서 130$0^{\circ}C$까지 떨어진 것이 관측되었다. 생성된 슬래그는 Quenching 부위에서 물에 의한 급랭으로 인한 열 충격으로 1~2 cm의 크기로 분쇄되었다. 실험결과 생성된 가스는 CO는 O2/coal의 비가 증가할수록 감소하였고, H2 및 CO2는 증가하는 것으로 관찰되었다. 생성된 가스의 발열량은 천연가스의(10,000 Kcal/Nm3)/약 1/8인 1700~1300 Kcal/Nm3로 측정되었다.

• Journal of the Korean Society for Heat Treatment
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• v.9 no.4
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• pp.229-233
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• 1996

This work has been carried out to reduce the softening of heat affected zone on laser surface alloying. Iron based rapid solidification material with $Cr_{5-10}$, $V_{1-3}$, $Mo_{3-7}$, $W_{2-5}$, $B_{7-8}$, $C_{2-3}$, $Si_{0.5-1}at%$ was alloyed on the surface of SM45C steel. The excellent softening resistance in alloyed and heat affected zone showed, which could be attributed to the formation of stable high temperature precipitates.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.108-111
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• 2001

YBCO HTS thick films coated using powder, Y$_2$O$_3$+L, quenched over 1200$^{\circ}C$ was studied. Quenched powder was crushed and mixed well in order to obtain uniformly dispersed Y2ll. Also, the powder was prepared with various condition in other to acquire optimum micro structure. As a result, it was found that the quenched sample on 1300$^{\circ}C$, holding time of 30min, has a bettor characteristic than other sample. On the other hand, the effect of film thickness was investigated. We concluded that the initiate film thickness has to be over 150$\mu\textrm{m}$. Especially, it was found that the film coated over 3 times with 50$\mu\textrm{m}$ m was best quality.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.110-111
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• 2014

Amount of slag which is a recycled aggregate that be produced as a industrial by-product from steel production process is increasing. But there is few suggestions for usage of slag except for shaft furnace slag and studies for utilizing this are lacked. In this study, it reviews flow characteristics according to replacement ratio of rapid cooling steelmaking slag from the perspective of rheology. Replacement ratio of ps ball is used by replacing 40, 45, 50% for each binder mass.