• Journal of the Korean Society of Safety
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• v.28 no.6
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• pp.23-28
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• 2013

In order to improve extinguishing performance of water mist, many studies of additives have been conducted. In this study, viscosity agent which has the ability to improve extinguishing performance by adhering to the surface on fire was used and fluorine-free surfactant was also added to water to enhance water's wetting ability. This study aimed to verify optimal concentration of extinguishing of additives according to fire source and extinguishing performance by comparison with pure water. In case of wood crib fire, the results show that flame suppression and extinguishing time of sodium alginate 0.4 wt.% are 3.4 times and 2.2 times shorter than those of pure water in 0.2 MPa respectively. It seems that large amount of water adhere to surface on fire, thus cooling effect on surface was enhanced. Also water consumption of sodium alginate 0.4wt.% is up to 65% lower than that of pure water. In case of heptane fire, extinguishing time of cocobetaine 0.1 wt.% is 9.7 times shorter than that of pure water in 0.2 MPa. It is thought that because cocobetaine can block oxygen and suppress oil mist by making emulsion film on fire surface due to a low surface tension. On the other hand, water consumption of cocobetaine 0.1 wt.% is 92% lower than that of pure water.

• Food Science of Animal Resources
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• v.38 no.1
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• pp.26-42
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• 2018

Today incorporation of natural ingredients as inorganic phosphate replacers has come into prominence as a novel research topic due to health concerns about phosphates. In this study, we aimed to investigate the quality of emulsified chicken meatballs produced with Jerusalem artichoke powder (JAP), either alone or in combination with sodium carbonate (SC) as sodium tripolyphosphate (STPP) replacers. The results showed that naturally dried JAP showed favorable technological properties in terms of water-oil binding and gelling. Emulsion batters formulated with JAP-SC mixture showed lower jelly and fat separation, higher water-holding capacity and higher emulsion stability than control samples with STPP. In final product, incorporation of JAP-SC mixture increased moisture and reduced lipid and energy values, and kept the pH value similar to control. Added JAP lead to increments in $b^*$ values whereas decreases $L^*$ values. Cook yield was similar to control in phosphate-free samples formulated with JAP-SC mix. Either low or medium ratios of JAP in combination with SC managed to protect most of the sensory parameters, while sensory scores tend to decrease in samples containing high levels of JAP. Addition of JAP to formulations presented samples that have equivalent behavior to phosphates in terms of lipid oxidation. In conclusion, our study confirms that utilization of JAP in combination with SC had promising effects as phosphate replacers by presenting natural solutions and providing equivalent quality to standard phosphate containing products.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.1
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• pp.67-74
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• 2000

Recently, PTFE-polymide composites are being used self-lubricating parts for industrial field. Thus, this study is mainly concerned with friction and wear properties for the piston ring of non-lubricating air compressor which made of PTFE-polymide composites. The friction and wear test was carried out for the different composition ratio under the atomsphere room temperature and constant load of 7.69N and their friction and wear properties were compared with each other at various sliding speed. notable results are summarized as follows. PTFE 100% showed that friction coefficient was almost same values at 0.94 and 1.88m/s but the value was decreased at 2.83m/s because the friction temperature is higher than low speed. PTFE 80%-PI 20% showed the lowest mean friction coefficient at 2.83m/s. PTFE 20-PI 80% showed the highest friction coefficient at 0.94m/s and the value was decreased at high speed but the value is higher than other materials except PTFE 100 %. PI 100% showed the highest friction coefficient at 0.94 and 1.88m/s becuase adhesive wear mainly occurred that speed. PTFE 100% showed highest specific wear rate on the whole. Specific wear rate of PTFE 80%-PI 20% was almost the same value with PTFE 20%-PI80%. PI 100%showed the lowest value at high sliding speed because the friction surface was thicken and carbonated by high friction temperature.

• Korean Journal of Pharmacognosy
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• v.15 no.3
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• pp.121-127
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• 1984

Attempts were to investigate the effects of 'Bojungikgi-tang' on the digestive system, blood pressure and diuresis. The results showed that relaxing action was shown on the isolated ileum in mice and that strong antagonistic actions were seen on $BaCl_2$, acetylcholine and histamine-induced contraction of the ileum in mice and guinea-pigs that the relaxing effect of the intestinal smooth muscle was recognized. Inhibitory effects on transport rate in the small intestine of mice and castor oil-induced catharsis in mice were noted. Inhibitory action on the secretion of gastric juice, pH ascending effect and decreasing effect of the free acidity and total acidity were recognized. Continuous hypotensive action was seen, but when the vagus nerve was cut, hypotensive action was remarkably decreased. The diuretic effect was also recognized.

• Journal of Sensor Science and Technology
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• v.17 no.4
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• pp.308-316
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• 2008

For the measurement of liquid level in ship's cargo tank, ballast tank, fuel oil tank and fresh water tank, several types of gauge meter are used such as tubular type, magnetic float type, reflex type transparent type and welding pad type. Among them, magnetic float type gauge meter is environmental friendly device because it is free of power source and maintenance. The main obstacle of the device is relatively large error bound. In this paper, finite element method is used to design and analysis of the magnetic float type gauge meter. The operation of reed switch according to the magnetic field has been successfully described and agreed well with experimental measurement. The optimum geometry with combination of permanent magnet and reed switches are designed to achieve 98 % accuracy of fluid level.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.19-24
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• 1991

Among the conditions changes for the slip melting point of tempering temperature and time were studied. The results were treated below at $4^{\circ}C$, slip M.P. were not effected by tempering time. But slip M.P. of lard and palm oil had fallen treated at $10^{\circ}C$, the reason was that low melting triglycerides did not form the perfect crystals. Therefore, in order to measure the slip M.P. should be decrease the free energy and from stable crystallization of fats. Recommendable tempering temperature was treated at $4^{\circ}C$.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.259-263
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• 2004

This study was conducted to investigate the growth rate and hematological changes of the rats when supplemented with the powdered tubers of chufa(Cyperus esculentus) for four weeks. Nutritional composition of the powdered tuber of chufa is crude lipid(22.3%), crude protein(7.0%), crude fiber(8.8%), ash(5.1%), nitrogen free extract(48.9%) and water(7.9%), respectively. Sixteen Sprague-Dawley male $rats(173.1\pm3.8$ g) were randomly divided into two groups, control group and chufa group. Rats in control group were fed with American Institute of Nutrition(AIN)-76 diet and rats in chufa group were fed with modified AIN-76 diet contained the powdered tubers of chufa at the proportion of 26% of total diet in order to substitute the oil content of AIN-76 diet. Final body weight, gain of body weight and feed intake of rats in chufa group were larger than those of rats in control group significantly. But feeding efficiency of rats in chufa group was less than that of rats in control group significantly. All hematological values such as hemoglobin concentration and hematocrit and serological values such as glucose, total protein, albumin, AST, ALT, cholesterol, high density lipoprotein-cholesterol and triglyceride were not significantly different between control and chufa group, respectively. Thus powdered tuber of chufa showed good tastefulness and did not provoke any adverse effect to the health indicators of rats. Therefore tuber of chufa would be used as new adequate feed resource for animals and possibly as suitable food resource for humans.

• Tribology and Lubricants
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• v.27 no.2
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• pp.57-64
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• 2011

Hybrid air-foil magnetic bearing integrates two oil free bearing technologies synergetically to adopt the strengths of two bearings with minimizing their weaknesses. This paper presents bending mode vibration control of a flexible shaft supported by the hybrid air-foil magnetic bearing. An experiment set-up of a flexible shaft supported by the hybrid air-foil magnetic bearing is built. In order to verify the effectiveness of the hybrid bearing, unbalance responses of the flexible shaft supported by three different bearings: air-foil, magnetic and hybrid bearings are compared. Effect of load sharing between air-foil and magnetic bearings are investigated through changing the control gain and the rotor center position of magnetic bearing. The experimental results shows that the hybrid bearing can control the bending mode vibration of the flexible shaft effectively and an optimal performance can be achieved with an appropriate load sharing between the air-foil and the magnetic bearings.

• Tribology and Lubricants
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• v.30 no.1
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• pp.1-8
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• 2014

In this study, a three-pad gas foil journal bearing with a diameter of 40 mm and an axial length of 35 mm was modeled to predict the static and dynamic performances with regard to an increasing mechanical preload. The Reynolds equation for an isothermal and isoviscous ideal gas was coupled with a simple elastic foundation foil model to calculate the hydrodynamic pressure solution iteratively. In the prediction results, the journal eccentricity, journal attitude angle, and minimum film thickness decreased, but the friction torque increased with the preload. A quick comparison implied a lower load capacity but higher stability for a three-pad gas foil bearing compared to a one-pad gas foil journal bearing. The direct stiffness coefficients increased with the preload, but the cross-coupled stiffness coefficients decreased. The direct damping coefficient increased in the horizontal direction but decreased in the vertical direction as the preload increased. These model predictions will be useful as a benchmark against experimental test data.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.88-92
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• 2009

The effect of Chlorella vulgaris (CV) on the urinary excretion of di-ortho PCB congeners (PCB-138, -153) was investigated. Sprague-Dawley rats (6-weeks-old, n=10 rats/group) were randomly divided into one control (0CV) or 2% CV (2CV) or 5% CV (5CV) or 10% CV (10CV) groups, respectively. Composition of normal and chlorella meal-based diet were made up of 30% casein, 15% cornstarch, 50% sucrose, 5% cellulose, 5% coconut oil, 3.5% mineral mixture, 1 % vitamin mixture. All rats had free access to water and diet for 4 weeks. A significant increase in both PCB 138 and 153 in urinary level was detected in CV fed groups, 540% and 167% for 2CV, 155% and 89% for 5CV, 114% and 144% for 10CV group, respectively, when compared with their controls. These findings suggest that CV may have potential to eliminate body burden levels of dioxin-like PCB compounds.