• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.194-198
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• 2008

The necessities of development of foundation having minimized occupying area and construction time are required for overpass in the downtown area by which bimodal tram will pass a crossway. We are studying a single column drilled pier foundation which is continuous from pier to pile foundation. Due to the increased resisting moment by reinforced steel which is ranged from the upper part of pile to lower part of column above ground, it can be possible to make a smaller pile-section and lessen the bar reinforcing. And for the excavation work is possible with smaller equipment, this foundation has a improved constructability and economical efficiency. This foundation needs smaller amount of concrete and has a small self-weight. It has an effect on improving resistance against earthquake due to improved ductility in addition to improved rigidity by interaction between concrete and steel.

• 약학회지
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• 제39권3호
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• pp.260-267
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• 1995

A lectin from the edible mushroom, Lentinus edodes, was purified through physiological saline extraction, ammonium sulfate fractionation and column chromatographies. On polyacrylamide gel electrophoresis, 0.05M fraction from hydroxyapatite column exhibited adjacent four sharp bands. The partially purified lectin agglutinated the erythrocytes of rabbit, mouse and rat, but not agglutinated human erythrocytes. The lectin's mitogenic effects were tested by its application to human and murine splenic lymphocytes. The results showed that the 0.05M fraction from hydroxyapatite was mitogenic, and the optimal dose of Lentinus edodes lectin was slightly lower than Con A by the culture with murine splenic and human peripheral lymphocytes. Meanwhile, its ability to agglutinate transformed cells was tested by its administration to continuous cell lines L1210 and HeLa cells. The leetin was found to be an agglutinin of tumor cell lines tested by L1210 and HeLa cells.

• 콘크리트학회지
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• 제20권2호
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• pp.25-36
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• 2008

Seismic design of reinforced concrete flat plate structures is often complicated as it deals with three dimensionality and continuous spans, and mostly material complexity and reinforcement variation. A great degree of uncertainty in such structural and material properties is thus inherent in the RC flat plate systems, and hinders simplification of the design process in terms of slab flexure, unbalanced moment transfer at a slab-column connection, and punching shear. For these reasons, there have been substantial changes and updates in building codes relating to flat plates and slab-column connections over a handful of decades. Also, for the same reason, some of codes never have been revised. As a consequence of nonsimultaneous development of each provision, it tends to confuse structural engineers when using a mixture of all different US code provisions. In this paper, in the step-by-step logical order, seismic design of the RC flat plate systems is re-organized and clarified to make it easier to apply. Furthermore, recent changes or proposed changes are introduced, and are explained as to how it will apply in practice.

• Nuclear Engineering and Technology
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• 제18권4호
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• pp.261-266
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• 1986

원자력발전소에서 사용되고 있는 증발기에 대해 boron의 탈비말 동반을 분석하기 위하여 강제순환식 및 반연속식 증발기가 실험에 사용되었다. 보수가 용이하고 제염효율이 높은 Cyclone과 glass-wool 충전탑을 액체방사성폐기물을 처리하는데 탈비말동반장치로 사용되었다. Cyclone과 glass-wool 충전탑을 연결하여 사용하였을 때 붕소에 대한 제염효율은 1,000 이상을 나타내었다.

• 콘크리트학회논문집
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• 제18권2호
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• pp.257-266
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• 2006

최근 공기단축, 낮은 층고, 자유로운 평면계획 등의 많은 장점을 가지는 플랫플레이트 구조형식이 고층주거건물의 구조형식으로 많이 사용되고 있다. 특히 국내에서 건설되고 있는 플랫플레이트 구조시스템은 횡력에 대한 저항성을 크게 하기 위하여 기둥의 단면이 매우 크며 직사각형 형태를 가지는 벽기둥(wall-column)을 사용하는 경우가 많으므로 접합부 강도산정모형에서는 이러한 기둥의 형태적 요소를 적절히 반영해야 한다. 기둥단면형상에 따른 플랫플레이트-기둥 접합부의 거동특성을 분석하기 위하여 기존의 강도모델을 검토하고 비선형 유한요소해석을 실시하였다. 기존 강도모델은 위험단면에서의 전단응력분포를 가정함에 있어서 기둥단면형상의 영향을 고려하지 못하여 플랫플레이트-기둥 접합부의 강도를 정확하게 예측하지 못하였다. 비선형 유한요소해석 결과, 하중가력방향과 평행한 기둥폭이 길어질수록 위험단면 측면에서 비틀림 전단을 받는 유효영역과 측면 최대전단강도가 줄어들어 접합부의 강도가 큰 폭으로 감소한다. 따라서 플랫플레이트-기둥 접합부의 강도를 정확히 산정하기 위해서는 하중가력방향과 평행한 기둥폭의 길이($c_1$)이 접합부 거동에 미치는 영향을 적절히 반영해야 할 것이다.

• 암석학회지
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• 제1권2호
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• pp.91-103
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• 1992

Eruptive mechanisms and processes at Udo tuff cone can be inferred from indicative characters of products, bedforms and lithofacies, and ring faults. In terms of bedforms and lithofa-cies in particular, massive lapilli tuff beds and chaotic lapilli tuff beds are derived from subaerial falls of aggregated tephra of wet tephra finger jets, occurring dominantly at the lower sequences of proximal part at the tuff cone. Crudely stratified lapilli tuff are derived from subaerial falls of slightly aggregated tephra of less wet tephra finger jets, whereas reversely graded lapilli tuff beds are from slightly disaggregated subaerial falls of continuous uprush. Both beds frequently occur in the middle sequences at proximal and near medial part of the tuff cone. Block and lapilli tephra lenses, ash-coated lapilli tephra beds(lenses) and thin-bedded tuff beds are derived from extremely disaggregated subaerial falls of dry tephra in the continuous uprush, frequently occurring at the upper sequences of medial part at the tuff cone. Udo tuff cone is a basaltic volcano emergent through the sea water surface while water could flood across or into the vent area. Emergence of the tuff cone was from the type-Surtseyan eruption characterized by earlier tephra finger jets and later continuous uprush columns of tephra with copious volumes of steam. Explosions began when boiling of wter produced a bubble column reducing the hydrostatic pres-sure, allowing exsolution of gases from the magma. This expansion of magma into a vesiculating froth fragmented the magma and permitted mixing of magma and water so that a more vigorous generation of steam could proceed. Tephra finger jetting explosions continued to build the crater rims, then remove water from the vent that their deposits flowed like slsurries until the continuous uprush explosion ensued. Continuous uprush explosions were associated with most rapid accumula-tion of tephra. The increasing volume rate led to partial removal of water from the vent area by the newly tephra ring so that more vigorous activity could be attended by a reducing water supply. This might restrain surplus of cold water entering the vent and thus enhance the vigour of the eruption by allowing optimal heat exchange. Eventually the crater became so deep and unsuported that piecemeal sliding, or massive subsidence on indipping ring faults, filled and closed the vent, and the cycle of explosions and collapse began anew.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권6호
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• pp.454-458
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• 2004

A study of the POSE (predispersed solvent extraction) for succinic acid by colloidalliq­uid aphrons was conducted. The organic phase contaning TOA (tri-n-octylamine) and 1-octanol permits a selective extraction of succinic acid from its aqueous solution. There was no difference of the extractability of POSE and that of conventional mixer-settler type extraction. Taking into account the no mechanical mixing in POSE, it was concluded that the POSE process is more adaptive than the conventional mixer-settler type extraction process. From mass transfer analysis at the various concentration of TOA in counter-current continuous operation, the concentration of TOA had no influence on the mass transfer coefficient. The loading values in continuous POSE were almost same as those in batch operation.

• KSBB Journal
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• 제8권5호
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• pp.417-423
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• 1993

생촉매의 수분함량이 기상에서의 연속반응기의 성능에 미치는 영향을 물질전달제한에 대한 연구와 함께 조사하였다. 각각 46.2%와 37.2%의 수분을 함유한 생촉매가 알코올 옥시데이즈 효소의 엠버라이트 IRA-400에로의 고정화 및 저속의 탈수화에 따라 준비되어져, 컬럼에 채워졌다. 연속식 기상반응에서의 상대생산속도(RPR)와 아세트알데하이드 조성($X_p$) 및 전환율(X)이 비교되었고 37.2%의 경우가 46.2%의 경우보다 우수하였는데 이는 기상에서의 물질전달 향상에 따른 것으로 판단되었다.

• 한국미생물·생명공학회지
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• 제25권1호
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• pp.68-74
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• 1997

The conversion of D-sorbitol to L-sorbose by Gluconobater suboxydans was analyzed, and continuous production of L-sorbose was carried out in immobilized cell reactors. L-Sorbose production by high densities of resting cells was more effective than by conventional batch fermentations. Sorbitol dehydrogenase, an enzyme converting D-sorbitol to L-sorbose, did not suffer from substrate inhibition, but from product inhibition. When L-sorbose production was carried out with Ca-alginate-immobilized cells, about 60 g/l of L-sorbose was obtained. On the other hand, when the corn steep liquor (CSL) concentration of medium was reduced to 0.08%, 80 g/l of L-sorbose was obtained. Outgrowth inside the immobilized carriers was thought to block the pores of the carriers so that substrate could not easily diffuse through the carriers. Continuous production of L-sorbose was well accomplished in a bubble column reactor, and 6. 5 g/l.h of productivity and 81.2% of yield were obtained at a substrate feeding rate of 0.08h$^{-1}$ under the optimum conditions with carrier volume of 55% and aeration rate of 3 vvm.

• 환경위생공학
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• 제13권1호
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• pp.174-184
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• 1998

Biosorption characteristics were investigated to discuss the use of agar entrapped Spirulina to remove of heavy metal ions from polluted waters. Agar immobilized algae were used as bioadsorbent in continuous reactor for heavy metal ions removal. The process solution contains Pb, Cu, and Cd as single ion and binary ions. In the adsorption of single heavy metal ions by agar immobilized Spirulina, the adsorption reached within 1hr and observed diffusion limitation differed from the free algal cell adsorption. The optimum pH for the adsorption of heavy metals was 4.5 but the influence of pH decreased less than that of free algal cell. Also, the adsorption characteristics of single heavy metal ions with agar immobilized Spirulina fitted the BET isotherm. Both of experiments of free algal cell and agar immobilized algae showed higher removal efficiency in the single ion solutions than binary ions solutions. The experimental results in the packed column with agar immobilized algae were over 90% of removal efficiency for the Pb, Cu, and Cd in single ion solutions.