• 대한기계학회논문집B
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• 제26권5호
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• pp.658-665
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• 2002

This paper presents a new winding method in electronic descaling (ED) technology. Conventional ED technology Produces an oscillating electric field via Faraday's law to provide the necessary molecular agitation to dissolve mineral ions. However, the proposed method produces an additional agitation force for mineral ions, called Lorentz's force. Experiments were performed using various Renolds numbers. A series of tests was conducted to measure the pressure drop across the test section and the overall heat transfer coefficient as a function of time. In order to accelerate the rate of fouling, artificial hard water, 1000ppm CaCO$_3$, was used throughout the tests. The results show that the new winding method accelerates the collision of the mineral ions, thereby improving the system efficiency. The present study can develope more effective fouling-removing equipment with change of estabishment method of coil.

• 대한가정학회지
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• 제23권1호
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• pp.19-24
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• 1985

The effect of temperature, washing time, mechanical agitation and concentration on the removal from cotton fabrics of tripalmitin labelled with C\sup 14\ were studied. In order to correlate the detergency with the removal mechanism, solubilization and suspending power of surfactants were observed. RESULTS : 1. The detergency from cotton fabric was increased with elevating temperature and over the temperature of maximum detergency, the rate of soil removal was rather decreased. 2. The effects of washing time and mechanical agitation on the removal of triplamitin were obvious at lower temperature. 3. The removal of tripalmitin was remarkably increased at higher concentration over cmc for all surfactants. The detergency of nonionic surfactant -NPPG- was best, this was resulted from its large solubilization and suspending power.

• 대한기계학회논문집B
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• 제29권2호
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• pp.239-246
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• 2005

Effects of subcooling on pool boiling heat transfer in vertical annuli with closed bottoms have been investigated experimentally. For the test, a tube of 19.1mm diameter and the water at atmospheric pressure have been used. Three annular gaps of 7.05, 18.15, and 28.20 have been tested in the subcooled water and results of the annuli are compared with the data of a single unrestricted tube. The increase in pool subcooling results in much change in heat transfer coefficients. At highly subcooled regions, heat transfer coefficients for the annuli are much larger than those of a single tube. As the heat flux increases and subcooling decrease, a deterioration of heat transfer coefficients is observed at the annulus of 7.05mm gap. Single-phase natural convection and liquid agitation are the governing mechanisms for the single tube while liquid agitation and bubble coalescence are the major factors at the bottom closed annuli.

• 한국수산과학회지
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• 제12권3호
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• pp.155-160
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• 1979

Lactic acid발효능이 있는 L. bulgaricus의 증식에 미치는 기계적 교반의 효과 및 동력학적 결과는 다음과 같다. 1) L. bulgaricus를 30시간 발효시켰을 때 세균의 농도는 액면변화가 적은 $N_{Re}=1\times10^5\~5\times10^5$ 범위에서는 2.4 UOD/ml로 동일 하였으며 $N_{Re}=1\times10^5\~1\times10^6$일 때 2.9UOD/ml로 가장 높은 값이었다. 2) 발효 30시간후 포도당의 잔량은 $N_{Re}=1\times10^5\~5\times10^5$범위에서 18g/l, $N_{Re}=1\times10^6$인 경우 8.3g/l였다. 3) 최대비증식속도$(\mu_{max})$는 $N_{Re}=1\times10^5\~5\times10^5$에서 $0.28hr^{-1},\;N_{Re}=1\times10^6에서 $0.58hr^{-1}이었다. 4) Saturation constant $(K_s)는 $N_{Re}=1\times10^5\~5\times10^5$ 3.44g/l, $N_{Re}=1\times10^6$에서 6.74g/l이었다.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 춘계학술발표회 초록집
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• pp.19-20
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• 2001

• 한국생산제조학회지
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• 제25권4호
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• pp.281-289
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• 2016

Agitation is a secondary process used to increase the PR stripping force on an ITO-glass surface; it is an efficient approach to stripping during production. It activates the stripper to chemically penetrate the PR layer and assists by breaking down the physical bonding forces at the surface. In this study, different stripping tests were conducted by varying the dipping time, the composition, the strip temperature, and the stripper concentration. Optimal PR strip conditions were estimated by using comparative visual inspection of stripped sample surfaces. The stripping process was affected by changes in the moving speeds and the sample positions. It was confirmed that the stripping capability improved at a dilute stripper ratio of 20-40% and a strip temperature of $30-40^{\circ}C$ and within 60 s of strip time.

• Korea-Australia Rheology Journal
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• 제16권3호
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• pp.153-160
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• 2004

Open microcellular foams having small-sized cell and good mechanical properties are desirable for many practical applications. As an effort to reduce the cell size, the microcellular foams combining viscosity improvers into the conventional formulation of styrene and water system were prepared via high internal phase emulsion polymerization. Since the material properties of foam are closely related to the solution properties of emulsion state before polymerization, the flow behavior of emulsions was investigated using a controlled stress rheometer. The yield stress and the storage modulus increased as viscosity improver concentration and agitation speed increased, due to the reduced cell size reflecting both a competition between the continuous phase viscosity and the viscosity ratio and an increase of shear force. Appreciable tendency was found between the rheological data of emulsions and the cell sizes of polymerized foams. Cell size reduction with the concentration of viscosity improver could be explained by the relation between capillary number and viscosity ratio. A correlative study for the cell size reduction with agitation speed was also attempted and the result was in a good accordance with the hydrodynamic theory.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.180-186
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• 2000

This paper presents a new winding method in the electronic descaling(ED) technology. The ED technology Produces an oscillating electric field via the Faraday's law to Provide necessary molecular agitation to dissolved mineral ions. But present method gives another agitation force to mineral ions, which is Lorentz's force. Experiments were peformed at various Renolds number. A series of tests was conducted, measuring pressure drop across test section and the overall heat transfer coefficient as a function of time. In order to accelerate the rate of fouling, artificial hard water of 1000ppm $CaCO_3$ was used throughout the tests. The results show that the new method accelerates collision of mineral ions and improvs efficiency of system.

• Tuberculosis and Respiratory Diseases
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• 제77권1호
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• pp.6-12
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• 2014

Severe sepsis is the most common cause of death among critically ill patients in non-coronary intensive care units. In 2002, the guideline titled "Surviving Sepsis Campaign" was published by American and European Critical Care Medicine to decrease the mortality of severe sepsis and septic shock patients, which has been the basis of the treatment for those patients. After the first revised guidelines were published on 2008, the most current version was published in 2013 based on the updated literature of until fall 2012. Other important revised guidelines in critical care field such as 'Clinical Practice Guidelines for the Management of Pain, Agitation, and Delirium in Adult Patients in the Intensive Care Unit' were revised in 2013. This article will review the revised guidelines and several additional interesting published papers of until March 2014, including the part of ventilator-induced lung injury and the preventive strategies.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.668-671
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• 2004

The mechanics of the dendrite fragmentation is a very important aspect of grain refinement in rheocasting. In this work, the stress field of the dendrite stirred in the semisolid slurry was simulated by Metlab 6.0 software. The result shows that stress concentration at the root of the dendrite arms is great enough to cause plastic deformation though the agitation is moderate. Accordingly, dendrite fragmentation was suggested to be caused by fractured after fatigue erosion.