• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.2
• /
• pp.472-477
• /
• 2017

Oil spills cause a lot of damage to the environment. Oil destroys the water environment and ecosystem in a very short period of time once they are contaminated by it, it takes a lot of time to recover from the contamination and the cleaning process is very difficult. Therefore, oil detectors are greatly needed as they can monitor any oil spills over the sea, rivers, and lakes. There are two kinds of technology available for detecting oil, viz. the contact and non-contact types. The former is based on the use of the conductivity, capacitance and microwaves, while the latter employs infrared, UV, laser, optic and radar technologies. As there are also various hurdles in the measuring of oil on water, such as the presence of waves, refraction of light, temperature and saltiness, it is imperative to select the right oil detector which is appropriate for the specific environment. In this study, a contact type oil detector is developed, which can be used in oil related industries, such as refineries, petrochemical companies, and power generation stations. The detector is made up of the sensor module, which floats on the water, and the controller which processes the signal coming from the sensor module and displays it. It is designed in such a way that the existence of oil is detected through the sensor and the change in the permittivity is observed to determine the volume and type of spilled oil.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.5 no.2
• /
• pp.147-159
• /
• 1995

This study was conducted to introduce fundamental data of hand-arm vibration and noise exposure levels with impact wrenches(double-hammer impact wrenches and oil-pulse impact wrenches) used in automobile assembly lines considering the process variables and tool variables. In studing, products per day, required time screwing the bolts or nuts per bolts or nut were considered as process variables, and capacity of bolts or nuts, air consumptions per minute, tool weights, RPM were considered as tool variables. Hand-arm vibration levels of 3 axis in each hand were measured using the instruments compling with ISO/DIS 5349 and noise levels were measured using a noise logging dosimeter. The results were as follows : 1. Required time to screwing the bolt or nut by oil-pulse impact wrenches is shorter than double-hammer impact wrenches but total daily exposure time of oil-pulse impact wrenches was higher than double-hammer impact wrenches because the number of bolts or nuts per cycle was many. 2. Oil-pulse impact wrenches have been used to screwing the large bolt or nut in comparing with double-hammer impact wrenches and required time to screwing the bolts or nuts were shorter than double-hammer impact wrenches because oil-pulse impact wrenches were using high RPM and large air consumption per minute. Noise level of oil-pulse impact wrenches was 8 dB(A) lower than double-hammer impact wrenches. 3. Dominant hand-arm vibration levels of double-hammer impact wrenches in each hand were $8.24m/sec^2$ of Zh axis in right hand and $9.60m/sec^2$ of Xh axis in left hand. Dominant hand-arm vibration level of oil-pulse impact wrenches in each hand was $2.59m/sec^2$ of Xh axis in right hand and $3.23m/sec^2$ of Yh axis in left hand. 4. In double-hammer impact wrenches, corresponding hand-arm vibration levels of Xh, Yh, Zh axis in left hand were higher than hand-arm vibration levels of right hand in 3 axis. In oil-pulse impact wrenches, Xh axis of right, Yh axis of left, Zh axis of left were higher than the corresponding hand-arm vibration levels of Xh, Yh, Zh axis in right and left hand. 5. Correlation coefficients among Xh, Yh. Zh axis of right and left hand hand-arm vibration levels in double-hammer impact wrenches and oil-pulse impact wrenches were commonly high in Yh axis and correlation coefficients of Yh axis in double-hammer impact wrenches and oil-pulse impact wrenches were 0.76 and 0.86,respectively. 6. As a measure repetitiveness, plotting total daily exposure time with the number of bolts or nut per cycle, direct correlation was shown between repetitiveness and hand-arn vibration exposure, and correlation coefficient between the number of bolts or nut per cycle and total daily exposure time in double-hammer impact wrenches, oil-pulse impact wrenches were 0.84 and 0.50, respectively. 7. Considering the total acceleration level and tool variables in double-hammer impact wrenches and oil-pulse impact wrenches, air consumption in right hand, and bolt or nut capacity in left hand were commonly the variable that explainability was high. Considering the noise and tool variables in double-hammer impact wrenches and oil-pulse impact wrenches, air consumption per minute was commonly the variable that explainability was high.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.54 no.11
• /
• pp.508-514
• /
• 2005

In this paper, it was investigated the characteristics of PD(partial discharge) pulse shapes in oil and the possibility of TF(Time-Frequency) analysis for the discrimination of air corona in on-site PD measurement of oil transformers. For the purpose, single and multiple discharges combined with oil discharges and air corona were generated and measured by use of artificial models through the HFPD pulse detector and the oscilloscope. PD pulse shapes were different according to the type of defects, especially including air corona- pulses. Also, through the TF analysis, data clusters could be classified each other in the TF Map, even in the case of multiple discharges. Therefore, it is known that TF analysis could be aprlied for the improvement of on-site PD measurement in oil transformers.

• Tribology and Lubricants
• /
• v.29 no.2
• /
• pp.77-84
• /
• 2013

A small engine-oil-deterioration detection sensor was developed and installed at the tip of a dipstick gage. The sensor part was manufactured using printed circuit board (PCB) manufacturing technology. A set of sensor covers was installed in order to protect the sensor and realize good signal stability. The small engine-oil-deterioration detection sensor system comprised a dual sensor having etched copper electrodes coated with gold and ceramic, a flexible PCB (FPCB) acting as electric wire, and a dummy PCB with only a lock connector. The sensor can easily be installed by insertion through the guide tube of a dipstick gage. Thus, a driver can easily handle it without further installation equipment. The sensor can determine the level of deterioration in the engine oil by estimating the corresponding dielectric constant of the engine oil.

• Journal of Nutrition and Health
• /
• v.26 no.5
• /
• pp.578-585
• /
• 1993

This study was performed to investigate effects of low fat diet and saturated fat supplementation on the function of the immune system. Forty male BALB/c mice average-weighing 15g were divided into two dietary groups: 0.7% safflower oil group and 4.3% beef tallow & 0.7% safflower oil group. Results are as follows; 1) Food intake, body weight, organ weight, agglutination test, differential white cell count and histological examination of spleen were not different in two dietary groups during the experimental period. 2) Delayed-type hypersensitive test of the mice fed 4.3% beef tallow & 0.7% safflower oil was significantly higher than that of the mice fed 0.7% safflower oil ($\alpha$=0.05). 3) Plaque forming cell was significantly reduced at 10th week compared to 7th week in both groups($\alpha$=0.05). Although there was no significant difference between two groups. 0.7% safflower oil groups showed slightly higher plaque forming cell than 4.3% beef tallow & 0.7% safflower oil group.

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

• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.6
• /
• pp.771-781
• /
• 1998

A highly compact and thermally efficient water cooled oil cooler for automotive use without offset strip fin and casing is developed in this study. The study result has shown that eliminating the fin and casing in the oil cooler the manufacturing process and cost and can be simplified and reduced greatly without sacrificing the thermal capacity. The oil cooler developed in the study uses the dimply type heat transfer core element design instead of offset strip fin and eliminates the outer casing for coolant water flow by applying specially made parallel loop flow design. In the study the thermal design program for the present oil cooler also was developed and validated experimentally.

• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.6
• /
• pp.754-762
• /
• 1998

Exhaust emissions in diesel engine are affected by fuel properties but the reason for this is not clear. Especially the recent strong interest in using low-grade fuel demands extensibe investigation in order to clarify the exhaust emissions. Bio-Diesel oil has a great possibility to solve the pollution problem caused by the exhaust gas from diesel engine vehicles. The use of bio-oils in diesel engines has received considerable atten-tion to the forseeable depletion of world oil supplies. So bio-diesel oil has been attracted with attentions for alternative and clean energy source. The purpose of this paper is to evaluate the fea-sibility of the rice-bran oil for alternative fuel in a diesel engine with rgard to exhaust emis-sions.

• Microbiology and Biotechnology Letters
• /
• v.14 no.5
• /
• pp.371-376
• /
• 1986

This study to elucidate concentrations of impurities such as methanol and fusel oil formed during fermentation process among the different materials and has been applied technical seperation for processing improvement by continuous distillation of super-allospas type. Methanol was formed high concentrations of cutting dried sweet potato and tapioca in order among the different materials during fermentation process. n-Propanol oil was formed high concentration of rice, cutting dried sweet potato, corn, naked barley and tapioca in order among the those materials. I-Buthanol showed high concentration of tapioca, corn, rice, cutting dried sweet potato and naked barley in order and isoamyl-alcohol showed high concentration of tapioca, rice, cutting dried sweet potato, corn and naked barley in order. Using the continuous distillation of super-allospas type, the following are collection ratios of n-propanol, iso-butanol, n-butanol and iso-amylalcohol: 37.9％, 28.6％, 37.4％, and 56.1％ when 78.25％ (v/v), 68.54％ (viv), 50.0％ (viv), and 50.0％ (v/v) alcohol are used, respectively. Fusel oil and bad alcohol put into the recovery column and then seperated directly by side cut of fusel oil partially from plate of tower bottom after concentration again. Extra impurities seperated by fusel oil seperator when 20 ％ (v/v) alcohol adjusted with water.

• Reproductive and Developmental Biology
• /
• v.38 no.3
• /
• pp.93-98
• /
• 2014

The objective of this study was to investigate the changes of oxidative stress and antioxidant enzyme during in vitro development with washing culture oil in porcine embryos. During the culture, the four types of culture oil such as paraffin oil with or without washing and mineral oil with or without washing were examined. The oil was washed with PZM-3 during 7 days and collected oil only. The embryos were stained with CellTracker$^{TM}$ Red, DCFDA and Hoechst 33342 to confirm the effects of the oil. As a results, Cleavage rates and total cell number were no difference among the four oil groups. However, ${\geq}16$ cell embryos were significantly different in fore type oil treatment and blastocyst rate was significantly higher washing paraffin treatment than in other group(p<0.05). Also, the expression of free radical were lower in washing paraffin oil than in other groups (p<0.05). On the other hand, the expression of glutathione were not significant different among paraffin oil with or without washing and mineral oil with or without washing, however washing paraffin oil and washing mineral groups were higher than other treatment groups. In conclusion, the washing oil was expected with positive effects on in vitro development in porcine embryos.