• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.77-78
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• 2002

A regression formula including the inlet film thickness as the parameter for the starvation factor in EHL condition is obtained by numerical analysis with Elord‘s cavitation algorithm. In addition, an apparatus for starved film thickness measurement by use of the white light interferometry is developed in order to verify the proposed regression formula. From observation results by this apparatus, the proposed regression formula can predict the reduction of central film thickness caused by starvation in a ball-plate contact with an uncertainty up to 10%

• Herbal Formula Science
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• v.14 no.2
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• pp.76-85
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• 2006

Objectives : We Investigated the effect of Dioscoreae Rhizoma(山藥) on the change of the corticosterone and the rectal temperature(直腸溫渡) of the mice induced by starvation stress(創戰 스트레스). Methods : After administration of Dioscoreae Rhizoma (0.25g/kg, 0.5g, 1.0g/kg, 3g/kg) three times, mice were starved. The corticosterone and rectal temperature were measured after 36.5 hours starvation stress. Results : The plasma cortiosterone levels in the S-2, S-3 and S-4 group were decreased significantly comparing with the control group (P<0.01) after 36.5 hours starvation stress. and rectal temperature was decreased in the control goup comparing with the normal group, but there is no significant change in the Dioscoreae Rhizoma treated group. Conclusion : it might be recognized that Dioscoreae Rhizoma has preventive-effect against starvation stress and also it might be needed further study in various viewpoints. Objectives : This study was disegned to elucidate the short term effect of Rossa rugosae Radix on proliferation. differentiation and maturation of 3T3-L1 Preadipocyte. Methods: 3T3-L1 preadipocytes obtained from Korean Cell Line Bank were cultured in a D ulbecco’ s modified eagle medium(MEM) culture solution containing 10% fetal bovine serum(FBS) and various concentrations of aqueous extract of Rossa rugosae Radix.. The short term effect of the extract of Rossa rugosae Radix on proliferation. differentiation and maturation of 3T3-L1 preadipocytes were investigate after treatment for 24 hours by measuring MTT. Oil Red 0 and latate dehydrogenase activity.. Results: The Rossa rugosae Radix extract inhibited significantly the proliferation of 3T3-L1 preadipocytes and tended to increase latate dehydrogenase activity in the media of differentiated 3T3-L1 preadipocytes & matured 3T3-L1 preadipocytes. the extract also inhibit the lipid accumulation of differentiated 3T3-L1 preadipocytes & matuered 3T3-L1 preadipocytes. Conclusions: These results demonstrated that the Rossa rugosae Radjx extract inhibited the proliferation. differentiation and maturation of 3T3-L1 preadipocytes. suggesting that Rossa rugosae Radix has anti-obesity effect: however further in vivo study is needed to demonstrate its pharmacological effects.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.5
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• pp.679-690
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• 1997

Oil spill over the sea and the river become a serious problem in these days. Two different approaches are used to clean up the spilled oil by means of chemical dispersion and mechanical devices. If it is possible, removing spilled oil using mechanical devices are highly desirable in order not to worry about the secondary contamination from chemical treatment. One of the major unsolved problems using mechanical devices has been the recovery of highly viscous oil spill. So, the systematic experimental data for treating very viscous oil are still wanting. In the present study a series of experiments were carried out to study the effect of the rotational direction of the belt skimmer on the rate of oil recovery using Bunker C oil. Three different situations, namely, upward, downward and up-and-downward pickup rate have been investigated for variable belt speed. The results showed that the rate of oil recovery for downward pickup was much higher than that for upward pickup. The major mechanism to recover the oil using a belt skimmer has been confirmed that oil sticks to the belt surface while moving to the water rather than moving upward. For the removal of spilled oil the optimal belt speed under the present experimental conditions was found to be about 200 ~ 270 mm/s just before the starvation started. The present experimental results would provide the basis for understanding the performance characteristics and physics of various types of skimmers.

• Journal of Aquaculture
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• v.11 no.4
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• pp.521-528
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• 1998

The influence of starvation on survival, growth and feeding incidence of larval tiger puffer Takifugu rubripes was investigated for 16 days after let them hatched at the temperature of 16.5~18.5${\circ}C$. The effect by delayed initial feeding on larvace was also studied. Almost all larvae began to be fed from the stage of yolk absorption about 5 days after hatching, in which rearing trials revealed that their survival and growth were influenced by food availability. Survival of unfed larvae, which stated to decrease drastically since the oil globule was exhausted about 9 days after hatching, dropped to 50% and 0% respectively on the 11.5th and 16th day. the difference of growth between fed and unfed larvae came into sight on about 5th day after hatching when the initial feeding was started, and had reduced in proportion to the length of starvation period. The condition factors for the unfed larvae were lower than thost of the fed. Of the larvae which had starved less than 5 days, more than 80% could consume food upon feeding. No fish had the ability in having food after 10 days. It appeared that the turning point of recover for the starving larvae came on 7th or 8th day. Their taking-food ability seemed to be affected by the change in swimming activity which depended on the duration of starvation. For the seed production of tiger puffer, therefore, feeding should be initiated as soon as possible, so as to enhance the production and survival of healthy seeds.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.114-120
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• 2000

Friction forces of piston rings for a typical SI engine were independently measured while excluding the effects of cylinder pressure, oil starvation and piston secondary motion using a floating liner system. Friction patterns, represented by the measured friction forces, were classified into five frictional modes with regard to the combination of predominant lubrication regimes(boundary, mixed and hydrodynamic lubrication) and stroke regions(mid-stroke and dead centers). The modes were identified on the Stribeck diagram of the dimensionless bearing parameter and friction coefficients which were evaluated at the mid-stroke and at the dead centers. And the frictional modes were estimated to the full operation range. The compression rings behave in the mode where hydrodynamic lubrication is dominant at the mid-stroke and mixed lubrication is dominant at the dead centers under steady operating conditions. However, the oil control ring behave in the mode where mixed lubrication is dominant throughout the entire stroke.

• Environmental Analysis Health and Toxicology
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• v.21 no.3 s.54
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• pp.267-273
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• 2006

Concentrations of four essential metals (Fe, Cu, Mn and Zn) were determined in apparently oil-polluted dead or near-dead three loon species collected in the Busan coast, Korea. Fe, Cu, Mn and Zn concentrations were generally high in liver, and also, Mn and Zn were high in bone. There were significant differences in some tissue concentrations of Fe, Cu, Mn and Zn among three species, but did not show any consistent evidence of species-specific accumulation. Mean concentration of Fe was 11,635$\pm$4010 $\mu$g/g, Cu 64.3$\pm$30.7 $\mu$g/g, Mn 13.1$\pm$2.32 $\mu$g/g, and Zn 121$\pm$24.8 $\mu$g/g in liver of all three species examined. Mn and Zn levels in this study were similar to those of normal loons and other seabirds reported from different countries. However, Fe and Cu liver levels were extraordinarily higher than those of reported. This result suggests that unusual accumulations of essential metals such as Fe and Cu may partially arise from long-term starvation due to oil pollution.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.4
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• pp.515-520
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• 2010

The response of broiler chicks to intubation of nutrients (starch, casein, soybean oil or their combinations) into the crop immediately after hatch was evaluated for performance, intestinal development, meat yield and immune competence up to 35 d of age. A control group with no access to feed and two test groups fed either inert material (sawdust) or starter diet for the initial 24 h after hatch were compared with nutrient intubated groups (n = 7). A total of 300 broiler chicks were equally distributed to 10 dietary groups with 6 replicates of 5 chicks each. After 24 h of hatch, all groups were fed ad libitum the starter (0-21 d) and finisher diets (22-35 d). Results indicated that post-hatch intubation of starch into the crop significantly (p${\leq}$0.05) improved body weight (at 14 and 35 d of age), readyto-cook meat yields, weights of breast muscle and small intestine segments, cell-mediated immune response, ND titers and weight of bursa compared to chicks starved or fed sawdust during the initial 24 h after hatch. However, chicks with access to feed immediately after hatch or intubation of starch, soybean oil, starch+casein, starch+soybean oil or starch+casein+soybean oil exhibited similar positive effects. Intubation of casein either alone or in combination with soybean oil was superior to the starved or sawdust fed groups, but inferior to other groups for all the parameters studied. It was concluded from the study that intubation of starch individually or in combination with casein and/or soybean oil effectively circumvented the negative effects of post-hatch starvation for 24 h. Among the nutrients intubated, carbohydrate (starch) was better utilized by the chicks than protein (casein) or fat during the initial post-hatch period.

• Tribology and Lubricants
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• v.33 no.3
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• pp.119-125
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• 2017

In this study, we perform a numerical analysis to predict the film thickness and lubrication regions for a thrust ball bearing under different operating conditions. Film thinning and replenishment affect the film thickness in starved lubrication. As the inlet meniscus position is brought to the edge of the Hertz contact, the thin film thickness is calculated as starved equation. We use a film replenishment model to determine the recovery film thickness between rolling elements. We use a hydrodynamic model to describe film recovery, that results from the effects of surface tension. In this model, we consider the surface tension gradient in fluid depression as the driving force for fluid recovery. We use Fourier transform method to determine the time-dependent depth of depressed oil. We calculate the change in the central film thickness graphically by using the recovery equation in starved elastohydrodynamic lubrication(EHL) under operating conditions that include numbers of balls, sliding velocity, applied force, and ambient film thickness. We evaluate the degree of starvation by using the distance from the center of the contact area to the meniscus position. Parched lubrication, a phenomenon where the film thickness decreases consistently, occurs at the severe condition. We determine optimal values with respect to the numbers of balls, and sliding velocity. The investigation can contribute to the design operating conditions for proper lubrication.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.19-26
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• 1993

In this study rats in fasting or fed protein free restricted diet including only fat showed much lowered level of serum cholesterol and triglyceride accompanied by utmost weight loss and high level of blood urea nitrogen indicated the tissue degradation, especially in liver with signs of damage or necrosis of hepatic parenchymal cell leading to elevated glutamic pyruvate transaminase value and to death. Rats fed only perilla oil in starvation or as fat source in normal diet dropped down the level of serum cholesterol and triglyceride compared to beef tallow fed rat. But with evidence of glutamic pyruvate transaminase values which was significantly elevated long term ingestion of perilla oil is likely to cause the lesion or any damage of hepatic function.

• Applied Chemistry for Engineering
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• v.25 no.6
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• pp.553-558
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• 2014

Microalgae are a promising alternative feedstock for biodiesel production because their growth rates and oil contents are higher than those of conventional energy crops. Microalgal lipid is mainly triacylglyceride that can be converted to biodiesel as fatty acid methyl esters through trans-esterification. In this paper, the influence of several important lipid inducing factors such as nutrient limitation and changes in salinity and metallic components in microalgae and their potential strategies to be used for biodiesel production are reviewed. Depending upon strains/species that we use, microalgae react to stresses by producing different amount of triacylglyceride and/or by altering their fatty acids composition. Although the most widely applied method is the nitrogen starvation, other potential factors, including nutrient surplus conditions and changes in salinity, pH, temperature and metal concentrations, should be considered to increase biodiesel productivity.