• International Journal of Ocean System Engineering
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• v.2 no.1
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• pp.32-36
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• 2012

This paper presents a comparison of potential and viscous computational codes for the water entry problem. A po-tential code was developed which adopted the boundary element method to solve the problem. A nonlinear free surface boundary condition was integrated to find new locations of free surface. The dynamic boundary condition was simplified by taking constant potential values for every time steps. The simplified dynamic boundary condition was applied in the new position of the free surface not at the mean level, which is the usual practice for linearized theory. The commercial code FLUENT was used to solve the water entry problem from the viscosity point of view. The movement of the air-liquid interface is traced by distribution of the volume fraction of water in a computational cell. The pressure coefficients were compared with each other, while experimental results published by other researchers were also examined. The characteristics of each method were discussed to clarify merits and limitations when they were applied to the water entry problems.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.2
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• pp.255-261
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• 2004

Antioxidant activity of extracts from the submerged-liquid culture of mushrooms was measured using two systems : linoleic acid and mouse liver microsomes induced by various free radical sources. Mushrooms of Pleurotus ostreatus (Neutari), Phellinus linteus (Sanghwang), Paecilomyces japonicus (Dongchunghacho), Hericicum erinacium (Norugungdengyee) and Agaricus blazei (Shinryeong) in 1% mulberry tree powder-supplemented medium were incubated in a shaking incubator (200 rpm, $25^{\circ}C$) for 3 days. Hot water extracts of mycelial cultures were freeze-dried, followed by fractioning with hexane, chloroform, ethylacetate and butanol in the order. Antioxidant activity of each sample was examined in free radical-induced linoleic acid oxidation in phosphate-buffered saline (PBS ) solution by measuring the amount of malonaldehyde (MA), and mouse liver microsomal systems by measuring the amount of thiobarbituric acid reactive substances (TBARS). In linoleic acid oxidation system, hot water extracts from the cultures of Pleurotus ostreatus, Phellinus linteus, and Paecilomyces japonicus exhibited stronger antioxidant activity than aqueous or butanol fraction and the combined fraction of hexane, chloroform and ethylacetate, but the hot water extract from Pleurotus ostreatus culture was the strongest activity. The antioxidant activity of the hot water extract from Pleurotus ostreatus culture was stronger than any other fractions in mouse microsomal system. These results suggest that hot water extract of Pleurotus ostreatus culture, and the cultures of Phellinus linteus and Paecilomyces japonicus could be useful for functional materials to reduce the oxidation of lipids in food systems induced by free radicals.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.693-698
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• 1997

Drought resistance and salt resistance of seedlings were compared with the polyethylene glycol(P.E.G) and NaCl solutions of the same osmotic potential($\Psi_\pi$=-10 bar). Plant height, seedling dry weight, chlorophyll content and leaf water potential decreased while the free proline content increased more in the P.E.G. than in the NaCl solution. Free amino acids increased 2.6 times in the P.E.G. solution and 3.6 times in the NaCl solution more than in the untreated(Hoagland's solution). Free proline occupied 66% and 61% of the content of total amino acids under water stress and salt stress, respectively. Besides free proline, phenylalanine in the P.E.G. solution and phenylalanine, alanine and asparagine in the NaCl solution increased distinctly. In short, it was shown that water and salt stress responses in seedling stage were relatively similar.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.4
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• pp.77-84
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• 2012

The lithographic process depends on a satisfactory ink-in-water emulsion being formed during printing and the speed of wet presses makes the choice of fountain solution vitally important as the ink and fount must react quickly to form a stable emulsion. Ink and water come into contact with each other on the rolls of the press and are forced together in the roll nips. The water is not soluble in the ink since it is slightly fat. Instead, an emulsion is formed, a heterogeneous mass consisting of small water drops mixed into the ink, if the water feed is too great. This emulsification can affect the properties of an off-set ink and negatively affect the printability. So we investigated the effects of the emulsification of phenol free heat-set ink and existing heat-set ink on printed quality, such as amount of ink transfer, printed density, print-through and uniformity. We used Duke emulsification tester for the emulsification of inks, and used IGT printability tester for printed quality. The printed quality were measured by densitometer and were evaluated by the image analysis system. Compared to conventional printing ink, phenol-free ink showed better results of the printability at the emulsification.

• Journal of Ocean Engineering and Technology
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• v.14 no.3
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• pp.35-40
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• 2000

SMAC method is, one of the numerical simulation techniques, modified from the original MAC for the time-dependent variation of fluid flows. The Navier-Stokes equation for incompressible time-dependent viscous flow is applied and, also marker particles which move with the fluid are used. Two-dimensional numerical computations of fluid flow are carried out in a virtual water tank. This paper has shown very well the movements of marker particles using SMAC method.

• The Korea Journal of Herbology
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• v.24 no.1
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• pp.15-21
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• 2009

Objectives : This study was designed to investigate the effect of water extract from Paeonia Lactiflora Pasll. with medicinal herb on plasma lipid and glucose in rats fed high fat diet. Methods : Experimental groups were divided into control diet group(C), high fat diet group(HF), high fat diet and 5% water extracts from Paeonia Lactiflora Pasll. with medicinal herb group(HFE I), high fat diet and 10% water extract from Paeonia Lactiflora Pasll. with medicinal herb group(HFE II). Weight gain, food intake, food efficiency, plasma lipid concentration and glucose were determined for 10 weeks during high fat diet. Results : In this experiment, body weight and food efficiency were significantly increase in high fat diet. High fat diet group showed elevated levels of total cholesterol, LDL-cholesterol and free fatty acid. Consumption of 10% water extract Paeonia Lactiflora Pasll. with medicinal herb lowers level of total cholesterol, LDL-cholesterol and free fatty acid. But levels of plasma triglyceride, HDL-cholesterol and glucose did not affect by high fat diet and water extract Paeonia Lactiflora Pasll. with medicinal herb Conclusions : In these results, water extract Paeonia Lactiflora Pasll. with medicinal herb in high fat diet group decreased plasma total cholesterol, LDL-cholesterol and free fatty acid. Thus the Paeonia Lactiflora Pasll. with medicinal herb might be useful in the treatment of hyperlipemia.

• Journal of Biomedical Engineering Research
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• v.20 no.2
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• pp.231-236
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• 1999

Understanding the exgenous water induced thermomechanical effect on the dental hard tissue by the Q-switched Er:YAG laser (1-$mutextrm{s}$-long pulse width) has an important impact on the further understanding of the free-running Er:YAG laser (250-$mutextrm{s}$-long pulse width) ablation on the dental gard tissue because one macroscopic effect in the free-running laser is an accumulation of microscopic effects we investigated in this study. The Q-switched Er:YAG laser with exogenous water on the tooth enhanced ablation rate compared to the case of no water on the tooth. The frequency of exogenous-water jet on the tooth has affected the ablation rate in such a way that as we dispensed water drops less frequently we could get more enhanced ablation rate. The amplitude of the recoil pressure depends on the tooth surface conditions such that as surfaces wet, and as the volume of the exogenous water drop increased, the amplitude of the recoil pressure increased also. From this study we realized that the 1 $mutextrm{s}$ long pulsed induced thermomechanical effect provides us useful information for the understanding of the free-running Er:YAG laser induced ablation with exogenous water.

• Journal of Ocean Engineering and Technology
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• v.25 no.4
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• pp.23-27
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• 2011

This experimental study was performed to find rpms of the impeller and the surface flow accelerator to make a uniform velocity vertical distribution in the circular water channel. PIV technique was employed to measure the water velocity profiles into the water depth from the free surface. The number of instantaneous velocity profiles was decomposed into mean and turbulence velocity components, and the distribution of velocity fluctuation and turbulence intensity were computed for each experimental condition. From these results, the velocity uniformity was quantitatively determined to present the flow quality in the measuring section of the circular water channel. It has been shown that the proper operation of the surface flow accelerator would make the uniform velocity profiles and reduce the velocity fluctuation near the free surface.

• Clinical and Experimental Pediatrics
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• v.50 no.5
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• pp.430-435
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• 2007

Even though we drink and excrete water without recognition, the amount and the composition of body fluid remain constant everyday. Maintenance of a normal osmolality is under the control of water balance which is regulated by vasopressin despite sodium concentration is the dominant determinant of plasma osmolality. The increased plasma osmolality (hypernatremia) can be normalized by the concentration of urine, which is the other way of gaining free water than drinking water, while the low plasma osmolality (hyponatremia) can be normalized by the dilution of urine which is the only regulated way of free water excretion. On the other hand, volume status depends on the control of sodium balance which is regulated mainly by renin-angiotensin-aldosterone system, through which volume depletion can be restored by enhancing sodium retention and concomitant water reabsorption. This review focuses on the urine concentration and dilution mechanism mediated by vasopressin and the associated disorders; diabetes insipidus and syndrome of inappropriate antidiuretic hormone secretion.

• Journal of Ginseng Research
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• v.5 no.2
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• pp.122-131
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• 1981

An aqueous extract s of fresh ginseng roots was heated at loot for 64 hrs. and the changes of color intensity, pH and the amount of free sugars and amino acids during the various intervals of the heating time were investigated. Color intensity and absorbance of the solution at 490nm were increased in proportion to the length of the heating time. Most of brown pigments produced during the treatment were water soluble, and pH 5.1 at initial stage of the solution, was slightly decreased at the final stages of the reaction. Sucrose, glucose and fructose were major free sugars in ginseng roots, and the amounts of sucrose was over 90 % of total free sugars. Sucrose. was largely decreased approximately 50%, by 64 hrs of the treatment, whereas sharp increase in the amount of glucose and fructose was observed during the reaction in the solution. The observed increase in reducing sugars, glucose and fructose was presumed due to hydrolysis of sucrose. Evidently, glucose and fructose were not important factor to control the browning reaction of the solution. Most of free amino acids and peptides except alanine and isoleucine especially arginine, serine and threonine, were sharply decreased up to 40 : 50% of the original concentration within 2 hrs. Accordingly, the content of free amino acids and peptides seems to be extremely important factor to control the browning reaction in ginseng. A free amino acid, presumed to be nor-leucine, was found in fresh ginseng root on the basis of re mention on liquid chromatography. Kinetic analysis of the browning reaction indicated a pseudo second order with respect to amino acid concentration at the initial stage.