• 상하수도학회지
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• 제28권4호
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• pp.441-451
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• 2014

The flushing is important to maintain good water quality in water main. It is a technique of using water velocity to remove sediments in water distribution system. The variety of water quality problems can occur in a distribution system, so too can a variety of benefits be gained by system flushing. In order to effectively perform the flushing, the contaminants to be removed to set up and it can be solved, it is necessary to ensure the proper flow rate. In this study, the removal of contaminants present in the inner water pipe attached loose deposits such as fine particles of granular activated carbon, sand and iron corrosion product sought to derive flow rates. Thus, the constant observation of using pilot plant scale water distribution plant for the movement of floating characteristics of particles were assessed.

• Korean Membrane Journal
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• 제10권1호
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• pp.33-38
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• 2008

In this study periodic water-back-flushing using permeate water was performed to minimize membrane fouling and to enhance permeate flux in tubular ceramic micro filtration system for Gongji stream water treatment in Chuncheon city. The filtration time (FT) 2 min with periodic 6 sec water-back-flushing showed the highest value of dimensionless permeate flux ($J/J_0$), and the lowest value of resistance of membrane fouling ($R_f$), and we acquired the highest total permeate volume ($V_T$) of 7.44L. Also in the results of BT effect at fixed FT 10 min, BT (back-flushing time) 20 sec showed the lowest value of $R_f$ and the highest value of $J/J_0$, and we could be obtained the highest $V_T$ of 8.04 L. Consequently FT 10 min and BT 20 sec could be the optimal condition in Gongji stream water treatment. Then the average rejection rates of pollutants by our tubular ceramic MF system were 93.8% for Turbidity, 20.7% for $COD_{Mn}$, 39.2% for $NH_3$-N and 31.5% for T-P.

• 한국산학기술학회논문지
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• 제12권2호
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• pp.623-628
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• 2011

마이크로 방전가공은 활용도가 높은 미세가공기술이지만 가공깊이가 증가하면 방전가공 시에 발생하는 가공부산물인 데브리(debris)로 인해 공구 전극과 공작물이 단락되어 방전의 진행이 힘들고 극심한 전극마모가 발생한다. 이를 극복하기 위하여 공구 전극이나 공작물에 진동을 부가하는 진동 플러싱 기술이 개발되었으나 기존의 진동 플러싱 연구는 피에조 액츄에이터를 적용하여 높은 진동수를 발생시키는 것에만 집중하였다. 본 연구에서는 경제적이면서도 유사한 효과를 얻을 수 있는 솔레노이드를 이용한 진동 플러싱을 제안한다. 솔레노이드를 이용한 진동 플러싱은 피에조 액츄에이터를 이용하는 것에 비해 큰 진폭을 얻을 수 있으며 진동수에 대해 독립적으로 설정하는 것이 용이하다. 가공 실험을 통해 솔레노이드를 이용하여 낮은 진동 주파수에서 큰 진폭으로 진동 플러싱하는 방법이 고주파진동 플러싱과 비교하여 경제적이며 충분한 적용효과를 발휘할 수 있음을 확인하였다.

• 한방안이비인후피부과학회지
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• 제37권3호
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• pp.99-109
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• 2024

Objectives : The purpose of this study is to report the effect of paljin-tang gamibang on facial flushing and xerotic eczema. Methods : We treated a 72-year-old female elderly patient who has facial flushing and xerotic eczema by korean medicine. She was treated from December 13th, 2023 to February 28th, 2024. The treatment applied was acupuncture, pharmacopuncture, herbal ointment and herbal medicine including 'paljin-tang gamibang'. The severity of symptoms was evaluated by photo comparison, visual analogue scale(VAS) and dermatology life quality index(DLQI). Results : After 11 weeks of treatment, the patient's symptoms improved. VAS of pruritus changed 10 to 1, VAS of dryness changed 10 to 1, DLQI changed 25 to 3. Conclusions : This case study showed an effectiveness of Korean medicine treatment including paljin-tang gamibang treated on facial flushing and xerotic eczema.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.310-313
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• 2003

The precipitation of heavy metals within the region of pH jump is inevitable in the conventional electrokinetic remediation technology. This study prevents the interest species from precipitating through the injection of flushing solutions in which HCl, acetic acid, citric acid, EDTA and SDS dissolved. The cumulative flow resulted from electroosmosis appear in order of Citric acid

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2013년도 춘계학술대회
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• pp.166-168
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• 2013

본 연구는 기존 필터의 Back-flushing에 의한 단점을 극복할 수 있는 Cross-flushing Type으로 설계하여 필터의 막힘을 순간적으로 재생할 수 있는 역세척 원리인 Cross flushing 방식으로 새롭게 고안하여 HYDAC 필터의 역세척이 가지는 단점을 근본적으로 보완한 새로운 형태의 Filter로서 필터의 막힘을 수직방향으로 강력한 와류세척에 의해 순간적으로 재생 시킬 수 있는 기능 가지고 있어 해수의 대용량 정밀여과가 가능하다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.635-640
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• 2003

Electrokinetic characteristic of natural soil dependent on flushing agents is studied to determine the best agent used in the hybrid electrokinetic remediation system. The soil containing 7.6% Fe$_2$O$_3$is spiked with lead. The flushing agents to be inject into anode are HCl, Acetic acid, Citric acid, EDTA and SDS. Test results showed that the early electrical potential of EDTA is lower than the value of the others. And the pH in anode reservoir is higher. Elcetrokinetic characteristic of all the sample except for EDTA is about the same.

• 한국식품저장유통학회지
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• 제4권3호
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• pp.265-270
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• 1997

Effect of modified atmosphere packaging conditions on quality changes of dry jujube was investigated. Dry jujubes with moisture content of 26.7% were packaged in PET/Al/PE film pouches with modified atmospheres. The tested packages include those with normal air, vacuum, CO2 flushing, N2 flushing and O2 scavenger. Packages were stored at 25$^{\circ}C$ for 6 months, during which ascorbic acid concentration, browning level, titratable acidity and surface color were measured. Generally modified atmosphere packages could improve quality retention of dry jujubes except that vacuum package resulted in large surface color change. CO2-flushed package showed the best quality retention of high ascorbic acid content and low browning during 112 days, but caused high amounts of ascorbic acid destruction and browning in longer storage. In all the modified atmosphere packages titratable acidity reached a maximum followed by decline and subsequent rise, while it increased linearly with time in normal air package. Considering ascorbic acid retention browning level and surface color changes during 112 days, the packages of CO2 flushing and N2 flushing were better than others.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.13-17
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• 2002

Ultrasonic waves have several mechanical, chemical, and biological effects on a saturated soil medium. Their mechanical effects, popularly known as cavitation. Cavitation is the rapid and repeated formation, and resulting implosion, of imcrobubbles in a liquid, resulting in the propagation of microscopic shock waves. In a soil-liquid system, their mechanical effects generate high differntial fluid-particle velocities and microscopic shock waves. The velocity perturbations are capable of dislodging oil in the system by overcoming the forces binding oil to sand particles. In this study, a series of laboratory experiments involving the simple flushing and ultrasonic flushing were carried out. An increase in permeability and oil removal rate were observed in ultrasonic flushing tests. Some practical implications of these results are discussed in terms of technical feasibility of in situ implementation of ultrasonics.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.183-185
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• 2004

In this study, the combined electrokinetic and ultrasonic remediation technique, ultrasonically enhanced electrokinetic technique, was studied for the removal of heavy metal and organic substance in contaminated soils. The electrokinetic technique has been applied to remove mainly the heavy metal and the ultrasonic technique has been to remove mainly organic substance in contaminated soil. The laboratory soil flushing tests combined electrokinetic and ultrasonic technique were conducted using specially designed and fabricated devices to determine the effect of these both techniques. A series of laboratory experiments involving the simple, electrokinetic, ultrasonic, and electrokinetic & ultrasonic flushing test were carried out. A soil admixed with sand and kaolin was used as a test specimen, and Pb and ethylene glycol were used as contaminants of heavy metal and organic substance. An increase in out flow, permeability and contaminant removal rate was observed in electrokinetic and ultrasonic flushing tests. Some practical implications of these results are discussed in terms of technical feasibility of in situ implementation of electrokinetic ultrasonic remediation technique.