• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.297-308
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• 2003

Subjective pork quality was determined on the six groups of the following treatments. Meat samples were obtained from pigs which had been fed with finishing pig diets containing 5% beef tallow(C), 3% beef tallow and 2% perillar seed oil(T1), 250ppm vitamin E($\alpha$-tocopheryl acetate) in T1(T2), 3% beef tallow and 2% squid viscera oil(T3), 250ppm vitamin E in T3(T4), 3% beef tallow and 2% CLA(Conjugated linoleic acid, T5). In the fatty acid composition, SFA(Saturated fatty acid) and EFA(Essential fatty acid) were higher in T5 than in the rest of three treatments such as C, T1, T3 groups, while UFA(Unsaturated fatty acid), MUFA(Monounsaturated fatty acid), UFA/SFA, MUFA/SFA were low. The total content of amino acid in the T3 were higher those for the rest of rest of C, T1, T5 the content for vitamin added treatment(T2, T4) groups higher than non treated one. T3 and T5 showed higher TBARS(Thiobarbituric acid reactive substance) values than the C and T1 groups VBN(Volatile basic nitrogen) values were higher in the order of T5>T3>T1>C. There was no difference in total plate counts, number of lactic acid bacteria and number of E. coli. In sensory property, the C and T1 showed a higher acceptance than the T3 and T5. In cooked meats, the T3 showed a lower hardness than that of control(C), T1 and, with a higher acceptance. In TBARS, VBN, total counts, lactic counts, and E. coli counts, sensory test of cooked meat and raw meat, there was no significant difference between vitamin supplement groups within each oil treatment.

• Journal of Korean Medical classics
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• v.21 no.4
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• pp.237-241
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• 2008

"난경(難經)"의 오유혈(五兪穴) 이론(理論)이 가장 많이 제기되는 문제는 '육십팔난(六十八難)'의 오유혈(五兪穴)의 주치작용(主治作用)이다. "영추 본수편(靈樞 本輸篇)"에서는 다만 오유혈(五兪穴)의 명칭과 위치에 대해서 소개하고 있지, 계통적인 주치에 대한 설명이 없고, '육십팔난(六十八難)'에서 명확히 5가지 종류의 질병에 대해서 귀납(歸納)하고 오유혈(五兪穴)이 주관하는 병증(病證)을 분별하여 후세의 모범이 되고 있다. 그러나 "난경(難經)"에서 오유혈(五兪穴)에 대해서 물이 흐르는 형상을 비유하여 사지(四肢)에서 체간(體幹)으로 향하는 노선으로 설명하고 있는데, 이는 "내경(內經)"의 십이경맥(十二經脈)이 여환무단(如環無端)하는 체계와 전혀 부합하지 않아서 학문과 임상에 있어서 지금까지도 혼란을 야기하고 있다. 그동안 "갑골문자(甲骨文字)"를 해독하기 위한 심도 있고 다양한 연구가 진행된 결과 고문자(古文字)의 해독(解讀)잘못된 계산식을 위한 공구서(工具書)들이 많이 개발되었는데, 본 논문은 그러한 고문자(古文字) 해독(解讀)의 연구방법(硏究方法)을 통해 "난경(難經)"의 오유혈(五兪穴) 이론(理論)의 난제(難題)를 해결하고자 한 것이다. 예를 들어 정형수경합(井滎輸經合)에 대해서 "난경(難經)"의 '육십팔난(六十八難)'에서 "소출위정(所出爲井), 소류위형(所流爲滎), 소주위유(所注爲兪), 소행위경(所行爲經), 소입위합(所入位合)"이라고 설명한 그 것 중에서 출(出), 류(流), 주(注), 행(行), 입(入)과 정(井), 형(滎), 유(兪), 경(經), 합(合)의 글자를 고문자(古文字) 해독(解讀)의 측면에서 재해석함으로써 이를 의학적(醫學的)으로 활용할 수 있도록 그 실마리를 제공하였다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.9
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• pp.2381-2389
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• 1993

In this paper the design and test results of a dynamic flow rate sensor was reported. This sensor comprises an 2-way cartridge valve as standard hydraulic component and a displacement sensor. Its working principle bases on the linear relationship between the flow rate and the piston displacement of 2-way cartridge valves under constant pressure drop. This principle is well known, however it is not easy to develop a flow rate sensor with the measurement range of 300 1/min, pressure loss of less than 8 bar at 300 1/min, maximum linearity error of less than $\pm$1% and the maximum rising time of 10 ms. This paper describes the design procedure of the flow rate sensor, the improvement procedure of static performance and test method and results of dynamic performance.

• Resources Recycling
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• v.17 no.3
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• pp.35-41
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• 2008

The study of coking technology to upgrade oil sand bitumen which is considered as alternative fuel was performed by using thermogravity analyzer and delayed coking reactor(600ml). To analyzed and compared coking characteristics of oil sand bitumen, the reactivities of oil sand bitumen were measured in the TGA. At the temperature conditions of $400{\sim}550^{\circ}C$ and the temperature rising velocity of $50^{\circ}C/min$. the termination time of coking reaction and conversion efficiencies increased with an increase of bed temperature. However the increase rate decreased over $450^{\circ}C$. So the coking reaction with oil sand bitumen might be over $450^{\circ}C$. Also the termination time decreased with increasing the temperature rising velocity. But the content of coke increased with increasing temperature rising velocity. At the experiments in the delayed coker, the temperature condition at maximum oil yield was $475^{\circ}C$ and the fuel properties of oil from coking reaction was almost equal with conventional diesel. It was verified that the coking process might be useful process to upgrade the oil sand bitumem by using API and SIMDAS.

• Tribology and Lubricants
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• v.38 no.2
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• pp.41-52
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• 2022

Mineral electrical insulating oil, which is widely used in transformers, exhibits excellent cooling performance and transformer efficiency. However, given that it is composed of petroleum-based components, it is weak in terms of biodegradability. This causes environmental problems in case of leakage and a low flash point, which is a factor that would cause great damage in the event of a fire in a substation. In this context, the use of eco-friendly electric insulating oil composed of bio-based vegetable oil and synthetic ester, which has excellent biodegradability and flame retardancy performance, has recently been expanded to the field of electric power, and various research and development (R&D) studies are in progress. According to different research results, vegetable oil and synthetic ester manufacturing technology, thermal stability, oxidation stability, property change, and quality control, which are characteristics of eco-friendly electrical insulating oils, are major factors affecting the maintenance of insulating oil properties. In addition, power companies have established and operated quality control standards according to the use of eco-friendly electrical insulating oil as they expand the exploitatoin of renewable energy in electricity production. In particular, deterioration and oxidation characteristics were jointly identified in R&D as an important influencing factor according to the content of saturated and unsaturated fatty acids present in vegetable oils and synthetic esters in power transformer applications.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.159-166
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• 2005

In Korea, although the generation of waste plastic has been increasing, the rate of recycling is considerably low and moreover, there is no suitable method for the treatment of waste plastics. However, pyrolysis, which is appropriate for the treatment of highly polymerized compounds, such as plastics, has recently gained much interest. In this study, a property of the products from the pyrolysis of mixed waste plastics, with a possible practical use for the recycling oil produced, were assessed. First of all, in order to investigate the pyrolysis characteristic of waste plastics, TGA (Thermogravimetric analysis) and DCS (Differential Scanning Calorimetry) were performed on a number of different plastics, including PP, LDPE, HDPE, PET and PS, as well as others. According to the result, it appeared that PP was the most efficiently pyrolyzed by changing the temperature, followed by LDPE, HDPE, PET, PS and the other plastics, in that order. From the results, the optimum conditions f3r pyrolysis were set up, and the different waste plastics pyrolyzed. The recycling oil produced from the flammable gases generated during the pyrolysis was com-pared with fuel oil by an analysis using the petroleum quality inspection method on KS(Korea industrial Standard). The results of the analysis showed the recycling oil was of a similar standard to fuel oil, with the exception of the ignition point, with a quality somewhere between that of paraffin oil and diesel fuel. With respect to these results, the quality of the recycling oil produced by the pyrolysis of waste plastics was suf-ficient for use as fuel oil.

• 한국해양학회지
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• v.26 no.4
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• pp.350-357
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• 1991

An experimental approach was applied to test the effects of stranded oils and dispersant cleanup on marine gastropods, Nodilittorina exigua, littorina brevicula and Purpura clavigera. They were exposed to Labuan crude, Dubai crude and Bunker C fuel oil. Direct oil contact caused death of gastropods within 96 hours. N. exigua and L. brevicula were more sensitive than P. clavigera at the exposure of Bunker C fuel oil. Toxic effects of Bunker C oil was slower than crude oils. direct contact to concentrated dispersant killed gastropods, while clean-up with diluted dispersant still gave severe damage. P. clavigera could escape from dispersed crude oil below 250 ppm. Oiling and dispersant clean-up may have severe effects on marine gastropods by rendering them washed out to sea.

• Journal of Power System Engineering
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• v.14 no.5
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• pp.5-9
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• 2010

본 연구는 수정 오일러 법칙을 이용한 봉의 열전달문제를 엄밀해와 수치해를 수치해석적 해법을 이용해 비교한 것이다. 경계조건으로는 열전도 및 대류가 동시에 존재하는 경우의 모델을 가정하여 계산하였고, 봉의 길이가 원주방향에 비해 상당히 길다고 가정하여 1차원으로 지배방정식을 정리하여 2차 상미분방정식을 유도하여 계산을 수행하였다. 계산을 수행한 결과 적절한 초기 추측값인 ${\beta}$값을 정의하면 오일러의 방정식으로도 충분히 만족할만한 결과를 얻을 수 있다는 것을 알았고, 지수함수 형태의 유도 상관식이 엄밀해와 ${\pm}1%$ 범위 내에서 일치한다는 결과를 얻었다.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.88-91
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• 2014

In this study, oil as a source of biodiesel from Nannochloropsis oceanica was extracted using organic solvent. The oil extraction yield and efficiency from dry and wet microalgae were investigated. The initial fatty acids content of the N. oceanica was 317.8 mg/g cell showing a high oil content over 30%. The yield from dry microalgae was higher than that from wet microalgae due to the inhibition of water. The yield by chloroform-methanol was the highest and the yield by hexane was the lowest. However, the total fatty acids contents with the chloroform-methanol were 678.7 and 778.2 mg/g oil under dry and wet conditions, respectively. The high oil extraction yield by chloroform-methanol reflected the fact that the extracted oil contained a high level of impurity. The hexane-methanol extraction from dry N. oceanica showed high oil extraction efficiency, 82.6%. The chloroform-methanol extraction under wet condition also showed high efficiency, 88.0%. While the hexane-methanol extraction from dry microalgae is desirable under low drying cost, the chloroform-methanol extraction from wet microalgae is desirable under high drying cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.264-274
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• 2019

This study attempted to analyze the effects of cleansing oil on skin by preferred vegetable base oil. For this, a questionnaire survey was performed against 100 people, and their face washing habit and preferred vegetable base oils were examined. Based on the results, 4 different cleansing oils were prepared and experimented. The experiment was conducted against 10 adult women in their 20-30s, and moisture level, sebum level and trans-epidermal water loss (TEWL) before and after the experiment were measured. After the test, satisfaction was measured, and the results found the followings: When asked what cleansing oil is most preferred by vegetable base oil type, 'rose hip oil' was the highest, followed by 'olive oil', 'apricot kernel oil' and 'camellia oil'. According to the clinical trials, both moisture and sebum levels increased before and after cleansing in all four cleansing oil types by the preferred vegetable base oil (p<0.001, p<0.001). In addition, TEWL decreased with a difference by base oil (p<0.01). According to a subjective satisfaction survey which was performed after the experiment, rose hip oil-contained cleansing oil (RHC) was the highest in terms of cleansing effect and satisfaction level. Consequently, it was confirmed that the cleansing oil by vegetable base oil improved skin conditions by protecting a skin barrier with a positive effect on the improvement of sebum and moisture levels and TEWL. Even though a preferred oil type and a satisfaction level may differ by preferred oil and feeling after use, cleansing oil by vegetable base can be helpful as a skin care product which eases skin dryness and protects a skin barrier.