• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.215-222
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• 1997

Flow experimental on not to be solid mortar which use Quenched Blast-furnace Slag as a fine aggregate was carried out for basic research data about fundamental study of application possibility of Quenched Blast-furnace Slag as a fine aggregate. It gives following result. The substitution rate is inversely proportional to Flow and C/S-rate same that. The relation with W/C-rate augment appear proportional : in case of C/S-rate, 1:3 increasing degree is a half of sand mortar that. Consequencely, Quenched Blast-furnace Slag motar is a counteraction to Flow in as same water content per unit. But suitable substitution rate and C/S-rate influence a little to the mortar consistency. And that reason, if C/S-rate and substitution rate will be regulated when we mix the mortar with quenched Blast-furnace Slag. that will be economic mixture.

• 대한조선학회지
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• 제18권3호
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• pp.59-63
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• 1981

With substitution with a delicate turn-tree instead of a long permanent cross-tree that is usally located on the derrick post, it is possible to get a large working range of the slewing angle 240 degree and also to decrease the slewing time of the derrick boom, comparing to the exisiting cargo gear system which has the same capacity of slewing winch.

• 한국국방경영분석학회지
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• 제12권2호
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• pp.1-21
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• 1986

Data Security in computer communication is becoming serious problem with developing computer network. This paper intended to design an encryption system to improve processing speed and to get higher degree of security by combining random number generation method, substitution method and Vernam's encryption method.

• 한국구조물진단유지관리공학회 논문집
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• 제26권5호
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• pp.95-102
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• 2022

최근, 전세계적으로 온실 가스의 저감에 관심이 높아지면서 건설 산업에서도 FA를 대량 치환하는 HVFAC의 사용을 위한 연구가 수행되고 있다. 시멘트의 수화도와 FA 반응도의 정량적인 측정은 HVFAC의 강도발현 메커니즘을 명확히 이해할 수 있게 한다. FA가 포함된 시멘트 페이스트의 수화 및 포졸란 반응은 매우 복잡하고 수화 생성물의 조성을 정확하게 결정할 수 없으므로 간단한 방법으로 반응도를 설명하는 것은 매우 어렵다. 따라서, 이 연구는 재령에 따른 하이볼륨 FA 시멘트의 수화 특성을 조사하였다. 시멘트의 수화도와 FA의 반응도는 재령에 따른 선택용해법과 페이스트의 비증발 수량을 통해 평가하였다. 또한 HVFA 모르타르 시편을 이용하여 연령에 따른 압축강도를 측정하였다. 실험결과 FA의 치환율이 증가할수록 시멘트의 수화도는 증가하나 FA의 반응성은 감소하는 것으로 나타났다.

• 동아시아식생활학회지
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• 제7권4호
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• pp.519-526
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• 1997

Propylene oxide와 반응시켜 치환도가 0-0.2645되는 하이드록시프로필화 감자 전분을 제조하여 이화학적 성질들을 측정하였다. 전분의 하이드록시프로필기 함량은 propylene oxide의 농도에 비례하였다. 하이드록시프로필화 감자 전분의 물결합력은 치환도가 증가할수록 증가하였고 pH는 치환도가 증가할수록 감소하였다. 청가와 요오드 흡착 강도는 치환도가 증가할수록 감소하였다. 시차주사열량계에 의한 호화양상에서는 하이드록시프로필화에 의해 전분의 호화온도가 낮아지는 것으로 나타났다. 하이드록시프로필화에 의해 전분의 상대 결정 화도는 낮아졌고, 전분 입자가 파괴되었음이 X-선 회절도와 주사전자현미경으로 각각 관찰되었다. 이것은 고농도의 하이드록시프로필화가 전분의 무정형 부분뿐만 아니라 결정성 영역에까지 영향을 주었음을 의미하였다.

• 한국식생활문화학회지
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• 제12권5호
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• pp.469-475
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• 1997

The modification of rice powder was attempted by treatment of acetic acid and epichlorohydrin to improve the functional properties of baby food. The initial gelatinization temperature of rice powder determined by amylograph was decreased from $79.5^{\circ}C$ to $63^{\circ}C$ by modification. The apparent and maxium viscosity of rice paste at $95^{\circ}C$ before and after modification were increased from 92B.U. to 236B.U. and from 100B.U. to 202B.U., respectively. The light transmittance of modified rice paste was increased from the temperature of $60^{\circ}C$ and by increasing the degree of substitution at the fixed temperature, while decrease more or less by the treatment of epichlorohydrin. The degree of retrogradation of the paste was decreased from 28.7 to 18.0 upon modification. The rate of syneresis of modified rice powder was decreased with increasing the drgree of substitution and ,the extend of epichlorohydrin treatment. Syneresis was not observed when acetylated rice powder whose DS value is 0.048 was treated with 0.25% of epichlorohydrin for the formation of cross-linkage. The addition of modified rice powder in preparation of semi-solid type infant food could improve the quality without lowering overall digestibility.

• 대한화장품학회지
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• 제42권4호
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• pp.433-440
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• 2016

본 연구에서는 수용액상에서 자기조립 나노입자를 형성할 수 있는 레티노익산이 접목된 양친성 폴리아미노산 유도체를 합성하였다. 합성한 양친성 폴리아미노산은 레티노익산의 접목도가 각각 5, 10, 30 mol%가 되도록 조절하였다. 수용액 상에서 양친성 폴리아미노산은 소수성 레티노익산의 분자 결합에 의해 안정한 자기조립 나노입자를 형성하였다. 자기조립 나노입자는 레티노익산의 접목도가 증가할수록 크기는 작아지고 형태는 구형에서 이중층 구조로 전이되었다. 또한 접목도가 10%일 때, 자기조립 입자의 구조 붕괴 없이 레티놀의 포집 및 전달이 가장 효과적인 것을 확인하였다. 접목도가 제어된 자기조립입자는 레티놀을 안정적으로 포집할 수 있기 때문에 주름개선제 및 다양한 기능성 화장품 전달체로 활용될 수 있다.

• 대한가정학회지
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• 제27권2호
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• pp.115-132
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• 1989

The household behavior of food, clothing, and shelter in Seoul area was analyzed to determine characteristics of consumer behavior in the industrial society. Questionaires were administered to 1095 housewives to find out the degrees and types of household labor substituted by the commodities and their buying behavior. Attitudes and values concerning clothing and housing were also measured. The results of the study indicated that the degree of labor substitution by commodities in clothing related area were high, while traditional food items were relatively low. Household labors related to clothing and housing maintenance also showed increased tendency to be substituted by the commercial services. The age and educational level of housewife, and household income were found to be the influencing factors to accelerated labor substitution, which is expected to increase as the industrialization progresses. Buying behavior varied in store selection and information sources according to commodities. Marketer dominated information sources according to commodities. Marketer dominated information sources were used for foods and clothing commodities, while interpersonal information sources were used for services. Shortened clothing life cycles, and rental housing were also found indicating consumer's change in housing concept from possession to use. Suggestion were made to consumers, industries, and government based on the results from the study.

• 한국식품조리과학회지
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• 제22권5호통권95호
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• pp.712-719
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• 2006

Sugar cookies using various levels of citron powder were prepared and the physicochemical and sensory characteristics were investigated in this study. The pH of the dough was relatively lower in the groups with increased citron powder. The yellowness of dough color was significantly increased from value of 23.47 to 36.99 as the substitution levels of citron powder content was increased (p<0.05). The degree of gelatinization of the dough measured using DSC was reduced with increasing delayed with the increased amount of the powder content. Cookies with powders content of 4-6 g showed significantly lower water contents than compared to those with 0-2 g(p<0.05). The spread factor tended to decrease as the substitution levels of the sample groups were increased. The results of sensory characteristics showed significantly higher bitterness and lower sweetness with the 6 g substituted sample group at (p<0.05). Desired citron cookie was prepared with the group of a substitution levels of 4 g citron powder from the confounded viewpoint of the physicochemical and sensory properties that were investigated.

• Macromolecular Research
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• 제12권1호
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• pp.71-77
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• 2004

We have synthesized various types of poly(ethylene glycol) (PEG)-ibuprofen conjugates by nucleophilic substitution of bromo-terminated PEG with ibuprofen-Cs salt. The conversion of the terminal hydroxyl groups to bromo-termini was quantitative, as was the drug conjugation process, which suggests that the present synthetic method is very useful for the preparation of PEG-based prodrugs from pharmaceuticals having carboxyl functionalities. The drug-release behavior of the prodrugs was examined in both phosphate buffer (PBS, pH 7.4) and rat plasma. From the drug-release behavior in PBS, we determined that each prodrug has high storage stability. The drug-release rate was observed to be much faster in rat plasma than in buffer solution as a result of the acceleration effect provided by enzymes present in the plasma. The drug-release rate in rat plasma depends on the degree of molecular aggregation of the prodrugs, which can be changed effectively by the nature of their spacer groups or by the use of Pluronic as the polymer carrier.