• Korean Journal of Ecology and Environment
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• v.49 no.2
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• pp.124-129
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• 2016

This study was conducted to suggest the cause analysis and mitigation measures of foaming generated in the effluent of wastewater treatment plant. The foam generated in the outlet connected with the tidal river system was identified as structural problems. And the main cause of foaming was air entrainment by an impinging jet and the internal accumulation by the diffusion barrier. In consideration of these conditions, it present the effective ways such as micro-screen and submerged outlet, to mitigate the foaming generated in the water channel and outlet end.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.4
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• pp.235-240
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• 2010

The foam produced by the effluent cooling water which is released to the discharge channel provokes civil complaints due to the visual pollution to the neighboring residents. In this study, a physical model test was conducted by placing tetrapods on the bottom slope of the discharge channel in order to suggest an effective method of reducing the amount of generated foam. Field application of the main results of the model test showed qualitatively apparent reduction of the foam generation at the discharge channel.

• Journal of Korea Port Economic Association
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• v.34 no.3
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• pp.183-200
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• 2018

This study empirically tests the presence of rational bubbles in the ship prices using time series data from October 1996 to April 2017. To detect the existence of ship prices' rational bubbles, we use integration and cointegration tests, which were proposed by Campbell and Shiller(1987) and Diba and Grossman(1988), for circumventing misspecification of ship price model and applying the bubble test to nonstationary time series. The result of integration test supports existence of tanker price's rational bubble. The co-integration test also shows that drybulk ship and containership prices have been overvalued relative to the market fundamental, drybulk and container freight rates, due to non-stationary rational bubbles. These results provide Korean shipping industry and authorities implications that anticyclical ship investment and long-term and steady fleet capacity expansion policy are needed.

• Proceedings of the Korean Fiber Society Conference
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• 1998.10a
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• pp.154-157
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• 1998

섬유공업에서 거품의 이용은 1960년대 부직포의 제조에 처음 시도되었으며, 기술개발 및 연구는 1980년대에 이르러서야 이루어지기 시작하였다. 거품을 이용한 염색가공 공정은 low wet pick-up을 하므로 건조하는 동안 약제의 이동이 적어 보다 개선된 염색가공 효과를 얻을 수 있고, 종래의 습식공정과 비교할 때 처리액의 가열 및 건조에 소비되는 에너지를 절약할 수 있다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.235-236
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• 2003

섬유의 습식 가공은 에너지 집약적 산업이다. 대부분의 에너지는 가공시 사용된 많은 양의 수분을 증발시키고, 건조하는데 소모되어진다. 따라서 거품가공은 물 소비를 감소시켜 에너지를 절약하고 폐수를 감소시키는데 주된 목적이 있다(1). 거품가공은 직물에 부가된 물의 양을 감소시켜 건조단계에서 상당한 에너지 소비(30~80%)를 감소시키는 것으로 알려져 있고(2~3), 최근에는 낮은 wet pick-up율에 의한 가공제 처리의 성능 및 수지의 가교분포에 대한 효과 등에 관한 많은 연구가 이루어지고 있으나 미흡한 점이 많이 보고되고 있다.(4~7) (중략)

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2001.10a
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• pp.375-378
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• 2001

현재까지 행해진 주식시장 거품에 관한 연구들은 주가를 형성하는 근본요인으로서 현금배당만을 고려하고 있다. 그러나 현금배당은 경영자에 의해 조정가능하므로 진정한 기업가치를 나타내는 신호로 보기 어렵다. 따라서 본 연구에서는 기업가치를 더 정확히 반영하기 위하여 기업의 자본상에 나타나는 자금변동을 고려한 '순현금배당'을 도입한다. 상태-공간 모형과 칼만필터링 추정법을 이용하여 KOSPI 시장 자료에 대해 실증분석한 결과, 현금배당만 고려할 때와 '순현금배당'을 고려했을 때 추정된 거품이 매우 다른 양상을 보였다. 특히 한국의 금융위기시점을 고려하여 볼 때 '순현금배당'을 이용한 것이 실제 현상과 더 잘 부합하는 것으로 나타났다. 이는 주식시장의 거품을 연구하는데 있어 현금배당과 자금변동을 함께 고려하는 것이 더 정확한 추정결과를 얻을 수 있음을 시사한다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.5
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• pp.472-481
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• 2008

In this study hydraulic experiment was carried out to investigate the flow characteristics in the submerged outlet structure of Boryeong power plant and the efficiency of bubble reduction by installing horizontal porous plate in the outlet structure. The cross-sectional mean velocity in the submerged outlet structure was smaller than 1 m/s, the target value at the design stage to prevent bubble outflow to the open sea area. In addition, it was found that the maximum depth of bubble penetration is reduced 30 to 50% by installing the horizontal porous plate at the second falling location in the submerged outlet structure. It is expected that the total bubble amount entrained in the water will be most efficiently reduced by installing square-hole-shape porous plate of 20 cm hole size and making its central section as non-porous structure to dissipate the energy of falling water.

• Korean Journal of Ecology and Environment
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• v.49 no.3
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• pp.187-196
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• 2016

This study was performed to improve the foaming generated in the effluent of wastewater treatment plant from March 2015 to July 2016. The main cause of foaming was air entrainment by an impinging jet and the internal accumulation by the diffusion barrier. Particularly, the foam growth was most active when there is low tide and larger discharge. To solve this problem, we experimented after installing fine mesh screen and the artificial channel device with underwater discharging outlet in the treated wastewater discharge channel and the outlet, respectively. As a result, the effects of foam reduction by devices ranged 85.0~92.0% and 70.7~85.6%, respectively. In addition, the foam and the noise were easily solved, first of all look to contribute to the prevention of complaints. Our device studies were applied to a single wastewater treatment plant. However, it is considered to be able to apply in other similar cases of domestic sewage treatment plants.

• 월간 한농연
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• s.73
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• pp.14-19
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• 2008

수입개방화의 가속화 속에서 우리나라의 농산물이 가격경쟁력을 갖추기 위해 농산물 유통단계의 거품 제거에 대한 요구가 거세지고 있다. 이런 가운데 얼마 전 농수산물유통고사(aT)에서 발표한 '2007년 주요 농산물 유통실태 조사 결과 분석' 보고서에 따르면 우리나라의 농산물 유통구조가 얼마냐 심각한 문제를 갖고 있는지 나타내고 있어 이번 호에서는 이를 바탕으로 우리나라 농축산물 유통구조의 문제점에 대해 다루어보려 한다.

• Proceedings of the Korean Fiber Society Conference
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• 1987.06b
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• pp.16-16
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• 1987