• Tribology and Lubricants
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• v.5 no.2
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• pp.21-31
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• 1989

최근 국내에서도 각종 공작기계 가공의 발전으로 말미암아 이에 쓰여지고 있는 윤활제의 이용범위도 점진적으로 확대되어 가고 있음은 물론 특히 Water계 윤활제의 요구성능은 점점 가혹하게 되어지고 있다. Water계 윤활제라고 하면 일반적으로 Cutting, Grinding, Drawing, Pressing, Heat Treating 등의 공작기계 계통의 Oil을 연상할 수 있겠지만 이들 이외에 각종 유압작동유를 비롯하여 Rolling Oil도 포함되고 있다. 따라서 본 논고에서는 근간 Crose up 되어지고 있는 Water계 윤활제 중 냉각압연유에 대하여 간략하게 기술하여 보고자 한다.

• Korean Membrane Journal
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• v.1 no.1
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• pp.43-49
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• 1999

Separation of soluble oil was investigated during filtration of cutting oil emulsion using various commercial ultrafiltration membranes. The surface properties of membranes used were hydrophilic hydrophobic and modified surfaces by various surfactant pretreatments. Conditions varied include stirring speed transmeembrane pressure membrane type and surfactant type for pretreatment. The results give some indication of mechanisms occurring at the membrane surface. Surfactant pretreatments significantly improved water flux and UF flux of hydrophilic regenerated cellulose(up to 2.4x for YM100) and hydrophobic polysulfone (up to 2.2x for PTHK) membranes depending on surfactant type and operating conditions. The UF flux enhancement was attributed to membrane swelling and reduction of interfacial surface tension between oil droplets and membrane surface. unexpectedly the hydrophilic membranes revealed greater flux enhancement than the hydrophobic membranes. The results also showed a greater improvement in UF flux at lower operating pressure.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.609-615
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• 2008

In this study, the design of UV-free reflecting reactor was studied to enhance the cutting fluid life for cutting machine. And also, the stability of cutting fluid with addition of biocide in cutting fluid and without biocide was compared with respect to the cutting fluid concentration, pH changes and microorganisms. Low number of microorganism was observed in the cutting fluid after UV-free reflecting treatment as compare to the cutting fluid which was added biocide and just cutting fluid alone. PH of the cutting fluid after UV-free reflecting treatment was about 9$\sim$8.5 while others were observed considerably low. The oil contents of cutting fluid which was added biocied and pure cutting fluid were almost degraded with the passage of time. However, in case of UV-free reflecting reactor, 4$\sim$3.5 Brix oil contents were observed in the cutting fluid.

• Safety and Health at Work
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• v.9 no.2
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• pp.180-183
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• 2018

Background: This research investigates the degrees of slipperiness felt by the participants who walk on contaminants applied to a floor surface to decide degrees of slipperiness for various contaminants. Methods: For the experiment, 30 participants walked on a floor to which six contaminants were applied. All participants took the analytic hierarchy process (AHP)-based slipperiness questionnaire survey for the six kinds of contaminants, and the results were compared with the coefficient of friction. Results: The results of slip risk from the AHP indicate that grease is the most slippery of the six contaminants, followed by diesel engine oil, hydraulic oil, cooking oil, water-soluble cutting oil, and water in a decreasing order of slipperiness. When the results of slip risk from the AHP are compared with the static coefficient of friction for each contaminant, the order of slip risk follows the same trend. Although the results of slip risk from the AHP coincide with the static coefficient of friction, further study would be needed to investigate this relationship. Conclusion: This study will contribute as reference material for future research on preventing industrial accidents that result in falls from high places due to slipping.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.1
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• pp.67-73
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• 2016

The application of titanium has been gradually rising because the utilizing ranges for low weight and high strength are rapidly increased by the need for improving the fuel economy in production industries such as the aviation and automotive in recent. The purpose in this study is to investigate the appropriate cutting conditions on the life of flat and round end mills by measuring the maximum cutting temperature relative to the machining time, and calculating the wear rates of cutting tool with the spindle speed and feed rate of vertical machining center as a parameter in the titanium roughing cut machining which is widely used in critical parts of aircraft, cars, etc. When the wetted roughing cut machining of titanium with a soluble cutting oil is conducted by the flat and round end mills, the maximum cutting temperatures for a variety of spindle speed and feed rate are measured at ten-minute intervals during 60 minutes by an infrared thermometer, and the wear rates of cutting tool are calculated by the weight ratios based on tool wear before and after the experiment. It is found that the maximum cutting temperature and the wear rates of cutting tool are raised as the cutting amount per tool edge is increased with the rise of feed rate, in this experimental range, and as the frictional area due to the rise of contacting friction numbers between tool and specimen is increased with the rises of cutting time and spindle speed. In addition, the increasing rate of maximum cutting temperature in the flat and round end mills are the highest for the cutting time from 50 to 60 minutes, and the wear rate of cutting tool in the flat end mill is 1.14 to 1.55 times higher than that in the round end mill for all experimental conditions.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.31-38
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• 1985

To learn more about the productivity of edible meat and its functional properties of spent hen, 60 White Leghorn fowls at 20 month of age were randomly divided into 6 groups, 10 hen for each group, and processed. As the productivity of edible meat, the yield of dressed carcass, giblets, cut-up meat, and breast and leg (thigh and drustick) muscles were determined. The approximate chemical composition, the content of salt-soluble protein, the emulsifying capacity and W.H.C. of breast and leg muscle were measured as the functional properties. The results were summarized as follows. 1. The average live weight of spent hen was 1,576.7g from which the yield of dressed carcass and giblets were 998.9g(63.4%) and 75.3g(4.8%) respectively. It means the yield of ready-to-cook form was 1,074.2g(68.2%) and the inedible byproducts was 502.5g (31.8%). 2. The average, weight of each part of cut-up chicken were: neck 41.0g(4.1%), wings 135.9g (13.6%), breast 276.7g (27.7%), legs 323.6g (42.4%). back 176.1g(17.6%) and the cutting-loss was 45.6g(4.6%). 3. The average weight of total edible muscle from breast and leg was 51.5g(85.86% of breast and leg cut weight) and the percentages based on the carcass and live weights were 51.6% and 32.7%, respectively. 4. The contents of H$_2$O, protein, fat and water-protein ratio of breast muscle were 72.95%, 20.54%, 1.59% and 3.55, respectively and those of leg muscle were 71.9%, 19.12%, 3.96% and 3.76%, respectively. 5. The salt-soluble protein contents of breast and leg muscle were 7.97% and 6.26% and their concentrations based on the total protein content were 38.8% and 32.74%, respectively. 6. The emulsifying capacity of breast and leg muscle was 43.23$m\ell$and 43.23$m\ell$, respectively. 7. The W. H. C- of breast and leg muscle was 54.23% and 52.61%, respectively.