• 한국염색가공학회지
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• 제20권4호
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• pp.43-52
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• 2008

Wool fabric was treated with oxygen low-temperature plasma (LTP) and dichloroisocyanuric acid. The effect of dimensional stability (relaxation shrinkage, hygral expansion, felting shrinkage), tensile strength and elongation, crease recovery, and hand of wool fabric between LTP, DCCA treated wool fabrics and control wool fabric were investigated. SEM photograph showed that a little micro crack was formed on the fiber surface by plasma treatment with hard condition and epicuticle scale was damaged by DCCA treatment. Felting shrinkage, tensile strength and total hand value were much different in each samples.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.43-45
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• 2008

According to industrial development, Ingots are more large and various. In particular large STS ingot. The probability of shrinkage cavity occurrence is higher than carbon steel and alloy steel. To manufacture ultra clean steel the technical development is nearly necessary for example controlling inclusions and total [H]. In this study, after measured the mold temperature and adjusted thermo conductivity of STS steel and compared existing mold to new one with CAE. As a result, the new mold more reduced than existing mold for the probability of shrinkage cavity occurrence.

• Journal of Ginseng Research
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• 제18권1호
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• pp.60-65
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• 1994

Fresh ginseng of same grade was stored under the 4$\pm$1$^{\circ}C$ and 87~92% RH for 10 weeks. During the storage, an aliquot amount of the ginseng was drawn, freeze dried and chemical constituents and physicochemical parameters were measured. After 10 weeks of storage drying rate and shrinkage of ginseng were 1520% and 9.04%, respectively, mold growth was seen at week 5 and observed for 51.2% of the ginseng week 10. Amylase activity level was elevated at the early stage of storage and decreased to 5% of initial value at week 5. At week 5, the elevated amylase activity was inconcomitant with the appearance of the mold growth. Crude protein contents were increased and decreased, respectively 5 week post storage. No significant changes in crude fat, crude fiber, ash, total sugar, n-butanol extract and ginsenoside were observed. The content of water-extractable substance showed maximum at week 7 to 8. The value of pH was slightly elevated and reducing sugar was increased during the storage. Key words Ginseng storage, physicochemical properties, drying rate, shrinkage, amylase activity.

• 대한토목학회논문집
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• 제33권2호
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• pp.729-737
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• 2013

콘크리트 포장의 환경하중은 온도하중과 수분하중으로 구분할 수 있으며, 이는 콘크리트 슬래브 내의 온도분포와 건조수축 및 크리프를 의미한다. 본 연구에서는 공항 콘크리트 포장의 역학적 설계에 필요한 환경하중을 산정할 수 있는 방법을 개발하였다. 먼저, 대상 지역과 설계 슬래브 두께를 결정한 후, 포장 온도 예측 프로그램을 사용하여 예측된 슬래브 깊이에 따른 콘크리트 온도분포를 등가선형 온도차이로 환산하였다. 기존 건조수축 예측 모형을 개선하여 지역별 상대습도를 고려하여 콘크리트의 건조수축을 예측한 후 부등건조수축 등가선형 온도차이로 환산하였다. 또한, 응력이완을 건조수축에 반영하였다. 결국, 온도에 의한 등가선형 온도차이와 수분에 의한 부등건조수축 등가선형 온도차이를 합하여 최종 환경하중인 총 등가선형 온도차이를 산정하였다. 적용 예를 보이기 위해 지역별 기상조건을 대표할만한 국내 민간공항 8곳 및 군공항 2곳의 환경하중을 본 연구에서 개발된 방법으로 계산하고 비교하였다.

• 한국건축시공학회지
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• 제7권1호
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• pp.107-113
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• 2007

This study investigates the filed application in Daebul Free Trade Zone applying both a flowing method using drying shrinkage-reducing superplasticizer(SRS) and an insulating curing method using double layer bubble sheet. Test results showed that fresh concrete satisfied target slump and air content. A structure adding SRS significantly decreased the total bleeding capacity and accelerated the setting time. As for the crack occurrence, the structure applying the flowing method and double bubble sheets simultaneously exhibited the most favorable crack endurance, while conventional concrete showed more than 1mm size of crack in overall. In addition, a structure applying the flowing concrete method partially presented the micro crack. For the area proportion of crack occurrence, the structure using the double bubble sheets indicated 9.8%, while others applying flowing concrete method was 28%, compared with that of conventional one. For the compressive strength of specimens, standard curing specimens indicated $3{\sim}33%$ higher value than that of specimens cured besides the field construction. The specimens containing SRS improved the strength of $2{\sim}6MPa$, which is $10{\sim}22%$ higher than that of conventional concrete.

• 한국염색가공학회지
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• 제12권2호
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• pp.103-110
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• 2000

To examine the physical properties of POY through the microstructure control, the crystal structure such as the crystallinity, the crystallite size, the orientation, the shrinkage, the tensile properties, and the thermal stress of POY(80/48, SD) were examined at different draw ratios and annealing temperatures. From the examination following conclusions were obtained : 1. The crystallinity was more effected by the heat setting temperature than by the draw ratio. The increasing rate was greatest at the heat setting temperature range of $170~190^\circ{C}$. 2. The crystallite size perpendicular to the fiber axis was more effected by the annealing temperature at lower draw ratios. On the other hand, the crystal and amorphous orientations were more effected by the heat setting at higher draw ratios. 3. The boiling shrinkage did not change significantly, but the total shrinkage showed 13% at the draw ratio 1.9 and the heat setting temperature $170^\circ{C}$. 4. The maximum thermal stress increased with increasing the draw ratio and decreasing the heat setting temperature in the temperature range of $170~210^\circ{C}$. At the draw ratio 1.9 and the heat setting temperature $170^\circ{C}$, the maximum thermal stress found was 1.1gf/d. 5. In the heat setting temperature above $170^\circ{C}$ after the drawing, the crystallinity, the crystallite size, the orientation, and the strength increased with increasing temperature, but the shrinkage and the maximum thermal stress decreased with increasing temperature.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.857-860
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• 2008

본 연구는 잠실제2롯데월드에 적용된 50, 60, 70MPa 콘크리트 강도에 대한 크리프 및 건조수축 특성 파악을 위한 재료연구의 일환으로 진행된 콘크리트 테스트 프로그램의 준비 단계에 대한 일련의 체계화된 과정을 나타내고 있다. 콘크리트 테스트 프로그램의 준비단계는 국내와 국외에서 진행되었다. S사 실험실에서 진행된 국내 진행일정은 총 5일간 진행되었으며 그 진행과정은 공시체 제작, 몰드탈형, 공시체 마킹, 수중양생, 포장, 및 운송으로 이루어져 있다. 국외에서는 PCA(Portland Cement Association)산하 CTL사에서 진행되고 있으며 테스트 항목은 탄성계수 측정테스트(정탄성 & 동탄성), 압축강도 테스트, 크리프 건조수축 테스트, 및 할렬인장강도 테스트가 진행되고 있다. 크리프 및 건조수축 실험의 경우에는 하중 재령일에 따라 총 18개월간 테스트가 진행될 예정이다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 추계 학술논문 발표대회 논문집
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• pp.13-16
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• 2006

This study investigates filed application in Daebul Free Trade Zone of a flowing method using drying shrinkage-reducing superplasticizer(SRS) and an insulating curing method using double bubble sheets. Test showed that fresh concrete satisfied target slump and air content. A structure adding SRS significantly decreased the total bleeding capacity and accelerated the setting time. As for the crack occurrence, the structure applying the flowing method and double bubble sheets simultaneously exhibited the most favorable crack endurance, while conventional concrete showed more than 1mm size of crack in overall, and a structure applying only the flowing method partially presented micro crack. For the area proportion of crack occurrence, the structure using the double bubble sheets indicated 9.8%, while others applying flowing method was 28%, compared with 100% of conventional one. Standard curing specimens had about $3{\sim}6%$ higher compressive strength than that of specimens cured at adjacent field construction. In addition, using SRS improved about $5{\sim}7MPa$, than that of conventional concrete at 91 days elapse.

• 대한기관식도과학회지
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• 제14권2호
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• pp.31-37
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• 2008

Background and Objectives: In most cases of benign neck cysts, surgical excision has been considered as treatment of choice. However, sometimes complete excision is very difficult, and recurrences has been occured due to insufficient surgery frequently. In this point of view, non-surgical treatment has been attempted with sclerosing agents such as picibanil(OK-432). In this study, we evaluated the efficacy of picibanil sclerotherapy for benign neck cysts. Materials and methods: We retrospectively reviewed 53 patients(27 males, 26 females) who had undergone sclerotherapy with picibanil for benign neck cysts such as ranula, lymphangioma, thyroglossal duct cyst and branchial cyst. Information was gathered with respected to age, sex, number of injections, side effect and outcome of treatment. All patients were treated with intralesional aspiration of cystic contents and injection of picibanil, and followed on neck ultrasonography or neck CT. Results: 53 patients received sonoguided sclerotherapy using picibanil(OK-432). 31 patients(41.3%) showed total shrinkage, near total shrinkage(more than 90% of volume) in 7 patients(9.3%), marked shrinkage(more than 70%) in 5 patients(6.6%) and partial shrinkage(less than 70%) in 17 patients. 15 patients(20%) reaveled no response and 8 patients showed recurrences with repeated sclerotherapy. The side effects of therapy were observed by symptoms such as fever, localized pain and odynophagia. However, these complications disappeared after several days in all cases. Conclusions: We recognized that picibanil(OK-432) sclerotherapy for benign neck cyst is a safe and effective procedures as a primary treatment before considering surgery.

• 콘크리트학회논문집
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• 제12권4호
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• pp.59-67
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• 2000

With increased height of structure, the effect of column shortening need special consideration in the design and construction of high-rise buildings. The shortening of each column affects nonstructural members such as partitions, cladding, and M/E systems, which are not designed to carry gravity forces. The slabs and beams will tilt due to the cumulative differential shortening of adeacent vertical members. The main purpose of estimating the total shortening of vertical structural member is to compensate the differential shortening between adeacent members. This paper presents effect of parameters for phenomenon of column shortening in vertical members. The paper presents effect of parameters for phenomenon of column shortening in vertical members. The conclusions obtained from this study are follow as ; Strength of concrete and steel ratio effected on column shortening caused by elastic and inelastic shortening. Also, it is known that Ultimate-shrinkage-Value, Specific-Creep-Value, and volume to surface ratio effected on inelastic shortening only. Particularly, Ultimate-Shrinkage-Value and Specific-Creep-Value effected considerable on the amount of total column shortening.