• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.521-524
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• 2003

This paper is aimed to develop the circuit of a coil-type oil sensor packaged to the automotive engine oil monitoring the deterioration in the driving condition and let a driver notify the optimized time for the exchange of engine oil. By applying the principle which the deterioration of automotive engine oil can be expressed to the dielectric constant, the capacitance bridge circuit and the integrator circuit are designed and packaged to a coil-typed engine oil. In this study. the range of operating temperature of engine oil is experimentally recommended within 55$^{\circ}C$ for the stability of a sensor designed. It is concluded that the characteristics of output voltage converted from the dielectric constant are linearly distributed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.451-454
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• 2003

The Oil Coolers is very important unit for the stable thermal performance in machine tools, semiconductor equipments and high precision measuring systems. To select a proper oil cooler for the temperature control of core unit in a machine, not only cooling ability but also static and dynamic sensitivity of temperature sensors are considered. In this paper, the relationship between cooling ability and inflow oil temperature is identified. The cooling ability is increased with the increase of inflow oil temperature. The oil temperature control errors of a cooler are influenced by mainly sensitivity of temperature sensors and heating velocity in a machine. The validity of error cause analysis for temperature control is proved by real cooling experiments with inflow and outflow temperature sensors.

• Journal of Power System Engineering
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• v.15 no.6
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• pp.41-46
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• 2011

Refrigerant oil reduces friction between piston and cylinder of compressor and is normally hard to mix or dissolve in refrigerant. Oil separator deprives refrigerating oil from mixed solution of refrigerant and refrigerant oil. Sometimes much machine oil is carried into an evaporator and is applied to surface of the evaporator, and then disturbs heat transfer through it. Well-made oil separator helps refrigerating system stable and evaporator sustain full capacity. In this paper, new oil separate with different way to structure is suggested and tested. As result the new separates is 13% higher at 0C with 10% mixture and 6% higher at 0C with 20% mixture.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.1
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• pp.50-58
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• 2003

An analytical study was carried out to investigate the performance of an oil pumping system of a variable speed compressor using a commercial CFD program. The simulations for the oil supplying system with the oil and air mixture were performed by varying compressor speed from 40 Hz to 90 Hz. Comparing the predicted with the measured data on the modified scroll compressor validated the simulation model. The predicted results were consistent with the test data with a maximum deviation of 12.8%. The oil flow rate significantly increased with a rise of compressor speed due to a higher oil flow rate from the swing pump and a greater centrifugal force on oil gallery.

• Korean Journal of Pharmacognosy
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• v.8 no.2
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• pp.69-72
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• 1977

The investigation is involved with the development of the new method of decoction preparation in order to prevent the loss of volatile oil from crude drugs. Volatile oil in crude drug containig volatile oil ranged from 1 to 2.2% in content. Volatile oil content in crude drung prescription which main component is a crude drug containing volatile oil was $0.11{\sim}0.39\;ml$. It was found that traditional method of decoction preparation has caused to lose almost all of the volatile oil. Application of method of Pharmacopoea (Kp II) for the preparation of decoction prevented the loss of volatile oil from one half to two-third of its content. The method of Pharmacopoea to which air condenser was attached could completely prevented the loss of volatile oil from the preparation.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.181-189
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• 1998

In order to investigate the effect of base oil composition on the electronic insulating oil's performances, an experimental study has been conducted using different oils. Owing to their properties, like lower pour point and gas absorbing, naphthenic base oils are used more often than paraffmic base oils for the electronic insulating oil application. Naphthenic and paraffinic base oils are significantly different in their aromatic hydrocarbon content. In this paper, PXE(para xylyl ethane), LAB(linear alkylbenzene), C13 aromatic hydrocarbon mixture and C17 aromatic hydrocarbon mixture are investigated regarding their influence on insulating oil's performances. According to present study, breakdown voltage decreased with increasing aromatic lydrocarbon content in a deep dewaxed paraffmic base oil. However, any changing in the dissipation factor was not recognizable at small treated level. Furthermore, the volume resistance was not influenced by aromatic hydrocarbon content. The gassing tendency was found as a highly sensible property, changing with treating aromatic hydrocarbons. The higher benzene ring content in the hydrocarbon, the better gassing tendency.

• Journal of Nutrition and Health
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• v.22 no.6
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• pp.466-475
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• 1989

This research was to investigate the effects of sardine oil with different antioxidants on tissue lipid peroxidation and the activity of superoxide dismutase in rats. Young male rats were fed for 6 weeks on different experimental diets containing 10% (w/w) sardine oil with $\alpha$-tocopherol (800mg / kg oil), $\delta$-tocopherol(1, 000mg / kg oil) or rosemary extract(1, 000mg /kg oil) as antioxidant and also sardine oil lard without antioxidant as control. In sardine oil group tissue lipid peroxide level and percentage of hemolysis were increased compared to those of lard group. By the addition of antioxidants, percentage of hemolysis reduced significantly but the lipid peroxide level in liver was unaffected. The activities of superoxide dismutase in erythrocyte and liver were not affected by either sardine oil ingestion or different antioxidants.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.113-114
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• 2016

In this study, various fats and oils were soaked in low-strength mortar to experiment what kind of fats and oils had the worst effect on low-strength mortar; it went as follows. For rate of change in length of fat and oil soaking, there was an increase in the order of pig fat, bio-diesel, grape seed oil, and water; in the case of olive oil it was destroyed within 56 days. For rate of change in mass, there was an increase in the order of bio-diesel, water, pig fat, grape seed oil, and olive oil. For relative motion elastic coefficient, there was a decrease in the order of olive oil, grape seed oil, and water. On the whole, pig fat, bio-diesel, and olive oil were shown to have the worst effect on low-strength mortar.

• Textile Coloration and Finishing
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• v.22 no.3
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• pp.257-263
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• 2010

Oil-absorbable nonwovens were produced by meltblown processing of polypropylene chips. In this study, experimental array and variance analysis of the design of experiment were used to increase the field repeatability and universality. Oil absorbency was decreased, as oil absorbable nonwovens of packing density and gearpump speed were increased. Oil absorption rate was increased, as packing density was increased. Also the oil absorption rate increased with increasing gear-pump speed.

• Journal of Biosystems Engineering
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• v.23 no.2
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• pp.125-134
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• 1998

It seems possible, by use of vegetable oils, to solve the pollution problem caused by the exhaust gas from diesel-engine vehicles. Recently vegetable oils has received considerable attention as an alternative and clean energy source to the foreseeable depletion of world oil supplies. The objective of this study is to experimentally investigate the characteristics of exhaust emissions of a small diesel engine using light oil, rice-bran oil, heated rice-bran oil, rice-bran oil treated with ultrasonic energy. SO$_2$ emission from the pure and the treated rice-bran oils was not detected at speeds hgher than 1,800 rpm while that from the light oil was detected at all the speeds at 4/4 load. NOx emission form these vegetable oils was generally higher compared to that from the light oil for most of the test conditions. tendency opposite to that of NOx emission. The data obtained in this experiment may be applicable for the desist of small diesel engine using the alternative fuels.