• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.3-8
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• 1998

The industrial revolution in England was based on the manufacturing systems by the power of water mill and rapidly progressed by the innovation of steam engine. It is no exaggeration to say that today's civilization is realized by the development of various types of power machinery, namely fluid machinery and heat engine. The electric energy is converted mainly from thermal energy (mainly steam) of mineral oil, coal and nuclear fuel through generator connected with steam turbine which is a kind of power machinery. There are various types of power machinery as shown in Tables 1a and 1b. They are classified into two types by use. One is absorption type of fluid and/or thermal energy, for examples, windmill and heat engine. The other is provision type of the energies for examples, pump, compressor and propulsion. By flow type, they are also classified by two types, turbo type and positive-displacement type. The turbo type began from water mill and windmill and evolve to steam turbine and finally to gas turbine. The positive-displacement type started from reciprocating water pump and developed into steam engine and changed to reciprocating combustion engine. The pumps and motors used in oil hydraulic system for power control are also positive-displacement type.

• Food Science and Biotechnology
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• 제18권5호
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• pp.1224-1229
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• 2009

The main objective of this study was to investigate possible application of citron (Citrus junos Sieb. ex TANAKA) seeds, which are massively produced as by-products during citron tea process, into functional food materials. First of all, citron seeds were germinated and produced citron shoots were examined for their functional properties. When contents of flavonoids in citron seeds and their germinated shoots were compared, naringenin, neohesperitin, and hesperitin were remarkably increased in shoots after germination while naringin and didymin were decreased. Concentrations of limonin and nomilin were decreased by germination otherwise their unidentified derivatives were newly formed. A methanol extract of citron shoot had lower $IC_{50}$ values [0.13 and 0.07 mg/mL for 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and ABTS, respectively] than citron seed extract in radical scavenging activities. Addition of 500 mg/mL of citron shoot extract suppressed fat accumulation in 3T3-L1 adipocytes by 36.9%. Oral administration of olive oil along with citron shoot extract (33 mg/kg body weight) to Sprague Dawley rats effectively inhibited absorption of lipid into a body by decreasing blood triglyceride levels from 105.1 to 74.9 mg/dL 2 hr after olive oil administration. According to these results, citron shoot extract as a rich source of flavonoids can be utilized for functional food ingredients with effective antioxidant and anti-adipogenic properties.

• 기술사
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• 제33권3호
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• pp.71-79
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• 2000

The effects of alkali salts adding on the cooking quality improving in dried noodles were investigated in the good texture maintaining for preventing solid soluble losses ,through chemical analysis and actual manufacturing practice ,the following results were obtained. Experiments were took a special flour of ASW:DNS=70:30, thickening agent(TA) composed of K2CO3 58%, Na2CO3 36% and Na4P2076%, and emulsified oil(EO) mixing of corn oil 44%, polysorbate 23%, emulsifier(ester of glycerin and fatty acids) 21%, soy lecithin 12%. When the mixing ratio of TA and EO to flour, is 0.03 and 1.5%(w/w) or morel than, satisfied the good quality. The water soluble solid matters content of the lowest 3.2% in the treating group that TA and EO is 0.03 and 1.5%(w/w) respectively, comparing to the 7.3% in the control group provides a excellent cooking quality. The research achieves the similar effects at specific gravity, water absorption ratio, weight increasing rate and volume expansion ratio. According to appearance test the more treating of TA turn the noodle into deeper yellow-green color. Turning to the deeper yellow color according to the increasing of EO provides better

• 폴리머
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• 제24권2호
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• pp.149-158
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• 2000

흡유성이 우수한 발포 폴리우레탄(EPU)을 제조하기 위하여 soft segment로는 친유성 polyol인 polypropyleneglycol (PPG)를 사용하고 hard segment로는 toluenediisocyanate (TDI)와 $H_2O$를 사용하였다. Soft segment 함량이 흡유성과 발포체의 기계적 특성에 미치는 영향을 조사하기 위하여 PPG 평균 분자량((equation omitted) 1000, 2000, 3000)에 따라 one-shot법으로 EPU를 제조한 결과 PPG 평균분자량이 3000에서 1000으로 감소할수록 흡유량과 인장강도는 각각 1460%에서 3010%, 0.26 $kg_{f}$ /$cm^2$에서 0.55 $kg_{f}$ /$cm^2$로 동시에 증가하였다. Hard segment 함량비인 (isocyanate index, r=[NCO]/[OH] r이 1.0에서 1.2로 증가할수록 allophanate와 biuret 결합 형성에 기인하여 EPU의 인장강도가 0.56$kg_{f}$ /$cm^2$에서 0.95 $kg_{f}$ /$cm^2$로 증가하였으나, surfactant (S-A)의 함량은 1.0 pbw에서 2.5 pbw로 증가할수록 closed cell 구조의 형성으로 인하여 흡유량이 3634%에서 3312%로 감소됨을 알 수 있었다.

• 펄프종이기술
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• 제47권5호
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• pp.112-119
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• 2015

The pulp mold attract the increasing concern as recyclable, biodegradable, and eco-friendly packaging materials. In order to broaden the applicability of the pulp mold as substitutes of the expanded styrofoam, the properties of various raw materials for the pulp mold were evaluated and the way for improving water resistance properties of the pulp mold were also tested by applying some additives. The higher value in the fines contents and in the water retention value were shown for the TMP (thermomechanical pulp), which resulted in the bulkier pulp mold with the higher moisture absorption property. In case of water resistance properties, the pulp mold made of white ledger stock showed the higher value in water contact angle and very slow water absorption rate. The addition of oil palm EFB fiber showed the improvement in the water resistance of the pulp mold made of UBKP. The effects of various additives on the improvement in the water resistance properties of the pulp mold were tested by using AKD, PVAm, epoxy resin. The application of AKD leaded to the higher increase in the water resistance. The results in this study showed the effects of AKD for the pulp mold could be improved and optimized by the application with fixing agent and by the ageing treatment after production.

• Asian-Australasian Journal of Animal Sciences
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• 제19권11호
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• pp.1623-1631
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• 2006

The objective of this study was to evaluate the effect of protein and energy on goats fed oil palm fronds (OPF) as roughages. Twenty-four male Saanen goats aged between 7 and 8 months and weighing $23.4{\pm}1.6kg$ were used in a $2{\times}3$ factorial design. Factors were three levels of urea (3%, 4% or 5%) and two levels of energy (low energy (LE) or high energy (HE)). On average, all parameters measured, including dry matter intake (DMI), nutrient digestibility, digestible nutrient intakes, ruminal ammonia-N ($NH_3$-N), ruminal total volatile fatty acid (total VFA) and individual VFA concentrations (mM/L), microbial N supply, P/E ratio and N retention were higher for HE compared to LE diets. Significant (p<0.05) interactions were found between levels of urea and energy for nonstructural carbohydrate (NSC) and energy (DE) digestibilities, ruminal $NH_3$-N and total VFA concentrations. HE diets had higher N absorption and retention than LE diets. Interactions between urea and energy for plasma urea nitrogen (PUN), heat production (HP), and urine and faeces N excretion were significantly lower (p<0.05) for the HE diets than those recorded for the LE diets. The results indicated that supplementation of energy enhanced utilization of urea and resulted in higher animal performance as a consequence of improved ruminal fermentation, microbial yield and N balance. However, the optimal level of urea supplementation remained at 3% in the HE diet.

• Preventive Nutrition and Food Science
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• 제13권3호
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• pp.204-211
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• 2008

Fish protein hydrolysates (FPHs) with different degrees of hydrolysis by treatment with alcalase, pronase, flavourzyme and trypsin and isolated peptide were prepared from Hwangtae (yellow dried pollack, Theragra chalcogramma). Hwangtae protein hydrolysate was fractionated according to the molecular weight into six major types of APO1 (1.3 kDa), APO2 (1 kDa), APO3 (<1 kDa), APACE (<1 kDa), APG1 (70 kDa) and APG2 (70 kDa) isolated from the hydrolysate using consecutive chromatographic methods. Soluble peptide were produced from Hwangtae and evaluated for their nutritional and functional properties. Some functional properties of FPHs were assessed and compared with those of egg albumin or the soybean protein. APO2 had the highest nitrogen solubility value (94.2%), emulsion capacity and emulsion stability of the Alaska Pollack peptide ranged from 12.4 to 39.5 (mL of oil per 200 mg of protein) and 44.0% to 77.5%, respectively. Highest and lowest fat adsorption values were observed for APG1 (9.9 mL of oil per gram of protein) and APO3 (3.8 mL of oil per gram of protein), respectively.

• 한국식생활문화학회지
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• 제14권1호
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• pp.49-55
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• 1999

본 연구는 우리 나라의 여러 가지 산채류 중에서 참취(학명: Aster scaber)를 이용한 스낵제품의 참취와 기름의 첨가 수준에 따른 이화학적 및 관능적 특성을 조사하여 최적수준을 알아본 것으로 요약하여 보면 다음과 같다. 참취와 기름의 첨가량에 따른 스낵의 이화학적 특성을 조사한 결과 L값(명도)은 참취의 첨가량이 증가할수록 낮아졌고, 기름의 첨가량이 증가할수록 높았다. 갈변도는 참취의 첨가량과 기름 첨가량이 증가할수록 감소하였다. 기름 흡수율은 참취의 첨가량이 증가할수록 크게 감소하였다. 팽화율은 참취의 첨가량이 증가할수록 감소하고 기름의 첨가량이 증가할수록 증가하였다. Texture analyzer로 측정한 스낵의 경도는 참취의 첨가량이 증가할수록 증가하고 기름첨가량이 증가할수록 감소하였다. 참취와 기름의 첨가량에 따른 스낵의 관능적 특성을 조사한 결과 어두운 정도와 참취향은 참취첨가량이 증가할수록 증가하였고, 기름첨가량이 증가할수록 약간 감소하였다. 경도는 참취첨가량이 증가할수록 증가하고 기름첨가량이 증가할수록 감소하였다. 바삭바삭한 정도는 참취첨가량이 증가할수록 감소하고 기름첨가량이 증가할수록 증가하여 경도와 반대 경향을 보였다. 기름진 정도는 참취가 증가할수록 감소하고 기름이 증가할수록 증가하였으며, 짠맛은 참취첨가량이 증가할수록 증가하였고, 기름첨가량이 증가할수록 감소하였다. 참취 스낵을 제조하기 위한 요인들의 최적 수준은 바람직한 특성인 바삭바삭한 정도가 5점 이상이고, 바람직하지 않은 특성인 기름진 정도가 5점 이하일 때 경제성을 고려하여 팽화율이 최대가 되는 처리 조합을 최적수준으로 결정하였다. 그 결과 최적 수준은 참취 8.6%첨가, 기름 7.6%첨가로 결정되었다. 본 연구 결과로 개발된 참취 스낵을 1일 약 70개(90g) 섭취할 경우 한국인 1일 영양권장량에서 권장하는 총 식이섬유량 20g의 1/2을 만족시키고 우리 나라 국민에게 가장 섭취량이 낮은(67%) Vitamin A의 권장량인 700 R.E.중 139 R.E.를 공급할 수 있으며, flavonoids 1.2mg도 공급할 수 있다. 따라서 참취 스낵의 이용은 노약자와 어린이 등의 섬유소를 쉽게 섭취할 수 없는 계층의 사람들이 쉽게 섭취할 수 있어 건강증진에 크게 도움이 될 것이며, 참취의 계절적 제약 및 저장기간이 짧은 단점도 보완할 수 있어 새로운 신토불이(身土不二) 식품개발로 인한 농가소득도 기대할 수 있을 것으로 생각된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.884-889
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• 2001

Combustion chamber crevices in SI engines are identified as the largest contributor to the engine-out hydrocarbon emissions. The largest of crevice region is the piston ring pack crevice. To predict and understand the oxidation process of piston crevice hydrocarbons, a 3-dimensional numerical simulation method was developed. A engine shaped computational mesh with moving grid for piston and valve motions was constructed. And a 4-step oxidation model involving 7 species was used and the 16 coefficients in the rate expressions were optimized based on the results from a detailed chemical kinetic mechanism for the oxidation condition of engine combustion chamber. Propane was used as a fuel in order to eliminate oil layer absorption and liquid fuel effect.

• Tribology and Lubricants
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• 제16권1호
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• pp.22-26
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• 2000

In this paper, the fuction of Zinc-dialkyldithiophosphate (ZnDTP) as an oxidation ingibitor of mineral oils was investigated and compared with 2,6-Di-tert-Butyl-4-Methylphenol (DBMP). Oxidation tests were conducted using an oxygen absorption apparatus. ZnDTP showedanti-oxidation property, and length of induction period prolonged by increasing ZnDTP concentration. The anti-oxidation property of ZnDTP was simmilar to that with DBMP. The amount of hydroperoxide decomposition ability with ZnDTP was much greater than that with DBMP, But the rate constant of radical scavenging with ZnDTP was less than that with DBMP. The anti-oxidation property of ZnDTP seems to by both synergy effect of hydroperoxide decomposition ability and radical scavenging ability.