• KSBB Journal
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• v.29 no.3
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• pp.179-182
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• 2014

The purpose of the present research was to evaluate the antimicrobial activity of the essential oil extracted from Pinus koraiensis seed against pathogens related to acne. The essential oil was extracted by steam distillation method. The chemical compositions of essential oil were analyzed by GC-MS. Alpha-pinene (29.87%), D-limonene (19.26%), betapinene (11.19%), beta-myrcene (3.84%), n-hexadecanoi acid (3.2%), beta-caryphyllene (2.72%), and cyclohexene (2.17%) were main components. This essential oil had antimicrobial activities against Malasseizia furfur, Propionibacterium acnes, and Staphylococcus epidermidis.

• Journal of the Korean Ceramic Society
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• v.33 no.8
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• pp.901-908
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• 1996

The oil-based magnetic fluids were prepared with synthesized ultrafine magnette by allowing surfactactants such as sodium oleate and aliquat 336 to adsorb on the surface of magnetite particles. The dispersion ratio of oil-based magnetic fluids was higher than 90% when the amount of sodium oleate and aliqua 336 were more than 2.63$\times$10-2 mol and 6.56$\times$10-3 mol for 20g of magnetite respectively. The dispersion ratio of oil-based magnetic fluids with the amount of secondary surfactant addition was higher than 90% when oil-based magnetic fluids were prepared with aliquat 336 of cationic type. However oil-based magnetic fluids prepared with surfactants of anionic and nonionic type showed lower dispersion than whose with cationic surfac-tants.

• Journal of the Korean Institute of Navigation
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• v.25 no.4
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• pp.423-433
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• 2001

As a part of the development program of Ulsan Port, construction of detached breakwater is planned. In Ulsan Port, several oil-buoys exist. If the detached breakwaters have been constructed, these oil-buoys will be located within 1 km from the planned breakwaters. Construction of the breakwaters gives rise to changes of wave conditions on the sea areas, especially in front of the breakwater and it affects mooring of tankers, which supply oil to the oil-buoy In this study, in order to calculate standing wave distribution after construction of a breakwater, numerical model is proposed based on unsteady mild slope equation. Calculation is performed by testing different wave heights, directions and reflection coefficients of breakwater. In addition, the influence to working condition of tanker moored at the oil-buoy is evaluated by using measured wave conditions and calculated results.

• International Journal of Fluid Machinery and Systems
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• v.6 no.1
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• pp.1-10
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• 2013

Jet pump is one type of artificial lifts and is used when depth and deviation of producing wells increases and pressure depletion occurs. In the present study, numerical analysis has been carried out to analyze the flow behavior and find the performance of the jet pump. Reynolds-averaged Navier Stokes equations were solved and k-${\varepsilon}$ turbulence model was used for simulations. Water and light oil as primary fluids were used to pump water, light oil and heavy oil. The ratios of area and length to diameter of the mixing tube were considered as design parameters. The pump efficiency was considered to maximize for the downhole conditions. It was found that the increase in viscosity and density of the secondary fluid reduced efficiency of the system. Water as primary fluid produced better efficiency than the light oil. It was also found that the longer throat length increased efficiency upto 40% if light oil was used as primary fluid and secondary fluid viscosity was 350 cSt.

• Biomedical Science Letters
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• v.23 no.3
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• pp.286-289
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• 2017

This study was designed to clarify the effect of juniper essential oil on the autonomic nervous system. Blood pressure and heart rate variability (HRV) reflecting autonomic nervous system activity were measured. The systolic and diastolic blood pressure were decreased by inhalation of juniper essential oil. High frequency (HF) power level, an indicator of parasympathetic nervous system activity was increased in the stimulation of juniper essential oil. High frequency/low frequency (HF/LF) ratio, an indicator of sympathetic nervous system activity was decreased by the juniper essential oil. These results suggest that juniper essential oil has a modulatory effect on the autonomic nervous system activity.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.7
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• pp.1003-1011
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• 2009

This study aims at precise control of oil outlet temperature in the oil cooler system of machine tools for enhancement of working speed and processing accuracy. PID control logic is adopted to obtain desired oil outlet temperature of the oil cooler system with hot-gas bypass method. We showed that the gains of PID controller could be easily determined by using gain tuning methods to get the gain of PID controller without any mathematical model. We also investigated various gain tuning methods to design the gains of PID and compared each control performance for selecting the optimal tuning method on the hot gas bypass method through experiments. Moreover, we confirmed excellent control performance with proposed PI controller gain even though disturbances were abruptly added to the experimental system.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.4
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• pp.578-587
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• 2009

In this paper, the characteristics of incompressible flow in a tube type marine fuel oil filter have been investigated. Fluent program has been used to obtain the solutions for the problems of three-dimensional, turbulent fuel oil flow in a filtering system. The inlet flow field is assumed to be uniform. The velocity and pressure distributions were obtained using Darcy's law. The increase of inlet velocity for cleaning fuel oil may cause some problems like vibration of the filter element. It was also required to consider the distribution of cleaning velocity because the worst distribution of cleaning velocity may cause the local insufficient cleaning effect and furthermore the effective filtration area can be reduced. The simulated results show that the computer code can be successfully applied for simulation of the complex base oil flow through the porous media. This paper could be applied to the design of auto-backwashing filtering system as design factor.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.5
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• pp.70-76
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• 2007

The purpose of this study is to analyze the characteristics of a domestic developed hydraulic axial piston motor. An experimental apparatus was constructed and the output torque, the input oil pressure, the input flow rate, the speed of motor and oil temperature were measured. They were measured under both no load and load conditions. The results are as follows; 1. Motion of motor became steady state conditions after 5 seconds. 2. Output torque of motor was proportional to input oil pressure under both load and unload. 3. Speed of motor decreased with increasing load. 4. Oil temperature was almost constant. The results of this study will offer the basic data in designing and operating hydraulic axial piston motors.

• Korean journal of food and cookery science
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• v.18 no.3
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• pp.340-348
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• 2002

Changes in the physicochemical properties of frying oil after single or repeated use in foodservice establishments were studied. The experiment was designed to simulate the practical frying practice based on a survey from the dieticians in the food service establishments. Used oils came from the single frying of mackerel and the sequential frying of 1) potato and mackerel, 2) battered pork and mackerel, and 3) potato, battered pork, and mackerel. The used oil samples were analyzed and compared with the fresh one. Oil quality parameters such as acid value, peroxide value, thiobarbituric acid value, iodine value, viscosity, and color were measured at each step of deep-fat frying. The physicochemical properties of the frying oils have been more or less affected by the frying conditions. However, the used oils resulted from the experimental trials were within the range of acceptance as indicated by the acid and peroxide values.

• Korean Journal of Plant Resources
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• v.10 no.3
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• pp.247-249
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• 1997

Seed protein and oil content is important trait in the soybean. Both seed protein and oil content in this plant species is inherited quantitatively. A 68-plant $F_2$ segregation population derived from a mating between Mercury and PI 467.468 was evaluated with random amplified polymorphic DNA (RAPD) markers to identify QTL related to seed protein and oil content. Marker OPB12 was found to be associated with differences in seed protein content. Four markers, OPA09b, OPM07b, OPC14, and OPN11b had highly significant effects on seed oil content. By interval mapping, the interval between marker OPK3c and OPQ1b on linkage group 13 contained a QTL that explained 25.7% variation for seed oil content.