• 제목/요약/키워드: Green Water

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CFD Simulation about Green Water on a Fixed FPSO in Regular Waves

  • Ha, Yoon-Jin;Nam, Bo Woo
    • Journal of Advanced Research in Ocean Engineering
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    • 제3권4호
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    • pp.174-183
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    • 2017
  • Numerical simulations were performed about the green water problem of a FPSO. Three regular waves in head sea were tested. A rectangular box-shaped FPSO was considered and it is assumed there is a vertical wall on the deck. For the numerical simulations, an open-source CFD code, OpenFOAM, was applied to solve the present problems. Focus is on wave fields around the FPSO, water flows and impact pressures on the deck. For the validation, the present calculation results were compared with the existing experimental of Lee et al. (2012) and Changwon university in KTTC Cooperative Study Report (2015). The statistical values and spatial distribution of the peak pressures are directly compared with the experimental data. Some discussions are made on the effects of the domain breadth on the Green water impact pressure.

디젤발전 자켓냉각시스템 열성능 향상 연구 (Performance Research of a Jacket Cooling Water System in a Diesel Electric Generation)

  • 이재근;문전수;윤석원;박필양
    • 한국수소및신에너지학회논문집
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    • 제20권6호
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    • pp.534-539
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    • 2009
  • One of the most efficient techniques improving the heat transfer performance of a diesel electric generation is a corrosion control in jacket cooling water system. The environmental parameters most affecting corrosion are dissolved salt concentration, temperature, and pH of cooling water. No corrosion occurs in carbon steel probe at pH 11 in normal operating condition of diesel electric generation cooling water. pH control agent in this study is trisodium phosphate. pH control appears to be the most convenient way to enhance the thermal performance of a diesel electric generation.

온실재배 풋고추의 소비수량(농업시설) (Water Requirement of Green Peppers in Greenhouse)

  • 이근후;이종창;윤용철;서원명
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2000년도 학술발표회 발표논문집
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    • pp.327-332
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    • 2000
  • This study was carried out to investigate the water requirement of green peppers which are cultivated in a greenhouse under the different soil water conditions. The meteorological conditions during the experiment period was not predominantly different from the conditions in a normal year. The highest leaf area per plant, plant height, and yield were 6,143$\textrm{cm}^2$/plant, 107cm, and 751g/plant, respectively. And daily variation of water requirements of green peppers ranged from 30 to 1,250g/d/plant which was fluctuated with significant difference. Total water requirements per plant which cultivated under the soil water conditions with different saturation ratios were 23,619g for P100, 43,044 for P80, and 2915g for P60, respectively. There were close correlation between plant height and water requirements. Low correlations were found between greenhouse ambient temperature and water requirement, while significant linear regression was shown between both of humidity and solar radiation and water requirement.

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녹차 추출물의 항돌연변이원성 (Desmutagenic Effects of Extracts from Green Tea)

  • 오창경;오명철;김수현
    • 한국식품조리과학회지
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    • 제16권5호
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    • pp.390-393
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    • 2000
  • Salmonella typhimurium TA98 streptomycin 의존성 SD510 균주를 사용하여 녹차의 수용성 추출물과 에탄을 용해성 추출물에 대한 항변이 효과를 검토하였다. 4-NQO에 대한 항변이 활성은 수용성 추출물과 에탄을 용해성 추출물 모두에서 추출물의 투여량이 증가할수록 높았으며, 억제효과는 5월과 8월 순 녹차 추출물을 1,000$\mu\textrm{g}$/plate 투여했을 때 각각 93% 및 95%로 나타났다. Trp-P-1에 대한 항변이 활성은 에탄을 용해성 추출물의 경우 53.3~921.%로서 투여농도가 증가할수록 억제 효과가 높았다. 그러나 수용성 추출물은 투여농도가 증가할수록 항변이 활성이 감소하였다.

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Durability enhancement of anion exchange membranes for water electrolysis: an updated review

  • Akter, Mahamuda;Park, Jong-Hyeok;Kim, Beom-Seok;Lee, Minyoung;Jeong, Dahye;Shin, Jiyun;Park, Jin-Soo
    • 한국표면공학회지
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    • 제55권6호
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    • pp.319-327
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    • 2022
  • Ion exchange membranes have been developed from laboratory tools to industrial products with significant technical and trade impacts in the last 70 years. Today, ion exchange membranes are successfully applied for water and energy for different electro-membrane processes. Hydrogen could be produced by electrochemical water splitting using renewable energy, for example, solar, biomass, geothermal and wind energy. This review briefly summarizes the recent studies reporting the state-of-the-art anion-exchange membrane water electrolysis, especially focusing on the enhancement of the durability of anion-exchange membranes. Anion-exchange membrane water electrolysis could be used as inexpensive non-noble metal electrocatalysts that are capable of producing low cost of hydrogen. However, the main challenge of anion-exchange membrane water electrolysis is to increase the performance and durability. In this mini review, the limiting factors of the durability and the technology enhancing the durability will be discussed for anion exchange membrane water electrolysis.

파래 분말을 첨가한 죽에 관한 품질 특성 (Quality Characteristics of Jook Prepared with Green Laver Powder)

  • 이미경;최상호;임홍식;안종성
    • 한국식품조리과학회지
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    • 제26권5호
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    • pp.552-558
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    • 2010
  • This study was performed to provide basic data on the use of green laver for jook. To accomplish this, we tested water content, color, brightness, mechanical qualities and sensory qualities in comparison to a control group. Higher concentration of green laver powder decreased water content, lightness, redness, viscosity and pH. Further, higher concentration of green laver resulted in lowered preference regarding appearance. However, better flavor was with the result of a higher amount of green laver. Therefore, green laver seems to have benefits for use in oriental soup. Accordingly, we expect there is potential for use of green laver for jook.

우수 시스템을 적용한 친환경 리모델링 방안 : 제주 국제공항을 대상으로 (A Case Study on Green Remodeling of Water System in Jeju Airport)

  • 김병현;나수연
    • 설비공학논문집
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    • 제19권6호
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    • pp.464-469
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    • 2007
  • The case study aims to propose the green remodeling strategies of water system in Jeju international airport facilities considering the environmental conditions of Jeju Island. The rain water was proposed as an alternative water source to conserve of under ground water resources. Computations of daily precipitation, rain collection, runoff and water usage was conducted to investigated the feasibility of the rain water system design.

수분(水分) : 점토비(粘土比)에 따른 주물사(鑄物砂)의 기계적(機械的) 성질(性質)에 관한 연구(硏究) (A Study on the Mechanical Properties of Molding Sand with various Water/Clay Ratio.)

  • 이계완;이추림
    • 한국주조공학회지
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    • 제4권2호
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    • pp.89-95
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    • 1984
  • A Study on the Mechanical Properties of Molding Sand with Various Water/Clay Ratio A standard sample of molding sand was prepared by adding a various amount of bentonite, which has water/clay ratio from 0.4 to 0.6, into artificial sand, Hanyoung #6. The results obtained by measuring the room temperature properties of green mold are as follows. 1. This compressive strength of green molds which have 4% and 10% of bentonite decreased with increasing water/clay ratio, but the maximum strengths of 4.3 (psi) and 7.2 (psi) were observed in the samples with 6%, 8% bentonite respectively when the water/clay is 0.45. 2. The optimum water/clay ratio for strength and permeability increased from 0.4 to 0.5 with increasing clay. 3. The green compressive strength was proportional to the hardness. 4. Deformation increased with increasing water/clay ratio. 5. Flowability decreased with increasing water/clay ratio and clay content in molding sand.

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플레어 각도에 따른 청수현상의 발생과정 및 갑판 위 유동특성 변화에 대한 실험적 연구 (Experimental Study on Variations in Behavior of Green Water and Flow Kinematics on Deck with Various Flare Angles)

  • 이강남;정광효;서성부;김문성
    • 한국해양공학회지
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    • 제32권2호
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    • pp.77-83
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    • 2018
  • In this study, a series of experiments were performed to investigate the variations in the behavior of green water generation and the flow kinematics of bubbly flow on deck with various flare angles. The experiments were conducted in a 2-D wave flume using a simplified model of a BW Pioneer FPSO operating in the Gulf of Mexico, with a 100-year return period wave condition. The green water phenomena were captured with a high speed CCD camera. The variations in the behavior of the green water generation were investigated with various flare angles, and the horizontal mean velocity profiles of bubbly flow on deck obtained using bubble image velocimetry (BIV) were provided. The differences in flow kinematics of bubbly flow on deck were analyzed with various flare angles.

An Experimental Analysis of the Impact of Green Water on Offshore Platforms with Green Water Protectors of Various Shapes

  • Lee, DongHyun;Jeon, MyungJun;Nguyen, Van Minh;Yoon, Hyeon Kyu
    • Journal of Advanced Research in Ocean Engineering
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    • 제2권3호
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    • pp.136-149
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    • 2016
  • Green water impact occurs frequently on offshore platform due to waves with a height greater relative to the freeboard of the structure. This phenomenon exerts a large impact load on the deck. In this paper, offshore platform models with green water protectors of various shapes were fixed to the center of a 3D wave tank to measure the impact pressure acting on the various points on deck and protectors. The impact pressure distribution differed depending on the protector shape, and various patterns of wave creeping up the protector were observed. The protector shape that exerted the lowest pressure impact on the deck will be useful in the deck design of offshore platform, and the model test results will be expected to be used for designers to select the best protector form.