• 한국결정성장학회지
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• 제11권5호
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• pp.197-202
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• 2001

여러 조건에서 제조된 poly(ethylene terephthalate) 필름 시편들로부터 열처리 및 냉연신 조건이 시편의 물성에 미치는 영향을 조사하였다. 상온에서 만능시험기을 사용하여 미열처리 및 열처리된 시편들을 0.5에서 500 mm/min의 cross-head 속도로 단계적 연신을 행한 결과, 약 50, 72 및 $129^{\circ}C$에서 열처리된 시편들의 응력-변형 곡선에서는 응력 진동이 발생되지만, 약 $83^{\circ}C$에서 30분 동안 열처리된 시편의 응력-변형 곡선에서는 응력 진동이 발생되지 않음을 알 수 있었다. 시차 주사 열량기를 사용하여 $10^{\circ}C$/min의 승온 속도에서 열분석을 행하였고, 시편들의 유리전이온도, 결정화 피크, 용융 잠열, 결정화도를 측정하였다. 1 Hz의 주파수대에서 $1.5^{\circ}C$/min의 승온 속도로 multiple-function internal friction pendulum으로 시편들의 동적 기계분석도 수행하였으며, 미열처리, 열처리 및 연신 시편들의 순서대로 탄성계수 값이 증가함을 알 수 있었다.

• Journal of Ginseng Research
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• 제32권2호
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• pp.127-134
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• 2008

This study was carried out to investigate the changes of ginsenosides composition in Korean red ginseng water extract (RGWE) after heated with high temperatures above $100^{\circ}C$. RGWEs were adjusted with pH 3.0, pH 7.0 and pH 10.0, respectively, and then heated at 100,110 and $120^{\circ}C$ for 30 minutes by using autoclave. Total ginsenosides of RGWE treated with heating showed decreasing tendency when compared with control. By TLC analysis, decreasing effect of ginsenosides in RGWE were significantly observed in the acidic condition of pH 3.0, particulary. By HPLC analysis, total ginsenoside of control showed 1.89%, while those of RGWE treated with 100, 110 and $120^{\circ}C$ showed 1.22, 1.05 and 0.97%, respectively. The ratio of protopanaxadiol (PD) to protopanaxatriol (Pr) saponins in control was 1.89, while that of PD/PT in treated RGWEs were level of 1.33 to 1.47. By the result of decreased ratio of PD/PT in RGWE, it was considered that PD type saponin such as ginsenoside$-Rb_{1}$, $-Rb_{1}$, -Rc and -Rd was more unstable than PT type saponin such as ginsenoside-Re and Rg against high temperature heating above $100^{\circ}C$.

• The Korean Journal of Ecology
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• 제18권4호
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• pp.483-491
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• 1995

This study examined the relationship among catch-fire, burning, maximum temperature (MT), amount of combustion-heat (ACH), and combustive time (CT) in heating temperature treated with the same amount of each organ of Miscanthus. In the survey sites, about 19％ of the areaswere covered by Miscanthus types, and the dry weight of Miscanthus and debris on the ground were 1,164 and 178 g/㎡, respectively. At 350℃ and 400℃, the rise of temperature by Culm type (culms and ears) and Leaf type (leaves and debris) were 90℃ and 82℃, respectively. At 350℃, durning time (BT) of culms-200, ears-200, ears-200, leaves-200 and debris-200 was 0-10’30”, 0-07’40”, 0-04’20”and 0-02’40”, and that at 400℃ was 0-01’20”, 0-00’50” 0-00’35”and 0-00’30”, respectively. BT was shorter at higher temperatures, and BT of Leaf type was shorter than that of Culm type. The amount of samples consumed was as follows: Culm type (culms-200 and ears-200) was 14.6g and 12.6g more than Leaf type (leaves-200 and debris-200) at 350℃ and 400℃, respectively. The total amount of combustion-heat (TACH) of samples was 5,859.7 kcal. The amount of mean combustion-heat generated from sample at 350℃ and 400℃ differed little: 727.6 kcal (24.9％) at 350℃ and 737.3 kcal (26.0％) at 400℃.

• Corrosion Science and Technology
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• 제5권1호
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• pp.1-4
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• 2006

Martensitic stainless steel is used when mechanical properties such as high tensile strength and hardness are required. Medium carbon-contained martensitic stainless steel which contains more than 0.2 wt% of carbon should be heat-treated and quenched at the temperature where undissolved carbides are totally dissolved into the matrix. In particular, the dissolution and reprecipitation behaviors of various forms of carbides are affected by such parameters as heating rate, heating temperature, duration time and cooling rate. This study is to investigate the effects of heat treatment parameters of 14Cr-3Mo martensitic stainless on corrosion resistance and phase transformation in relation to the dissolution and reprecipitation of carbides.

• 한국식품과학회지
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• 제53권1호
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• pp.92-98
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• 2021

The effects of heat-moisture treatment (HMT) on rice flour (RF) have been investigated for possibility of texture modifier in protein-based foods matrix, tofu. The optimum condition for preparation of tofu with maximum textural parameters was investigated by using response surface methodology (RSM). Rice flour was subjected to moisture content (10-30%) and heating temperature (100-140℃). Based on the response surface and superimposed plots, the optimized conditions of hydrothermally treated rice flour was as followed: moisture content, 22%; temperature, 130℃, which showed lower swelling power as compared to native RF and became more stable during continuous heating and agitation than native one. Tofu, prepared with HMT-RF, showed a denser network structure than that with RF, thereby inducing an increase in textural parameters. From the above results, the addition of HMT-RF could preserve the quality of tofu and be useful for developing an acceptable protein-based food product.

• Journal of Welding and Joining
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• 제25권4호
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• pp.28-34
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• 2007

The heating unit of direct heating method manufactured as the plasma spray coating of $TiO_2/NiCr$ conductive heating material on the surface of heating unit in order to improve the disadvantages of indirect heating method. $TiO_2$ and NiCr (80wt.%Ni-20wt.%Cr) that had the properties of conduction and heating was chosen for the conductive heating material. The compositions of the composite powders were studied $TiO_2-30wt.%NiCr\;and\;TiO_2-10wt.%NiCr$. As the heating temperature was increased, the hardness of heating layer was increased because of the fine microstructure and the decrease of porosity. The adhesion strength was decreased for coarsening and connection of voids in the insulation layer, and the electrical resistivity of heating layer was increased for fine crack formation and growth. In this study, the best efficient sprayed coatings with heating unit was concluded as the plasma sprayed $TiO_2-10wt.%NiCr$ coatings that was heat treated at $300^{\circ}C$.

• 한국식품과학회지
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• 제10권1호
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• pp.88-91
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• 1978

식중독(食中毒) 세균인 Salmonella enteritidis와 S. typhimurium에 방사선과 열(熱)($45^{\circ}C$ 또는 $50^{\circ}C$에서 10분)을 병용(倂用)처리한 바, 처리순서에 따라 살균작용에 현저한 차이가 나타났다. 방사선조사(照射)후에 가열한 것은 상승효과를 보였으나 방사선조사(照射)전에 가열한 것은 오히려 반대 효과를 보였으며 그 영향은 가열온도에 따라 다소 차이가 있었다.

• Journal of the Korean Wood Science and Technology
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• 제33권4호통권132호
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• pp.30-37
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• 2005

라디에타 파인 유령목의 수지를 제거하고 재색을 변화시킬 수 있는 열처리와 증기처리 방법의 적정 조건을 찾기 위해 본 연구를 수행하였다. 공시판재는 두께 20 mm와 30 mm를 사용하였다. 열처리는 $150^{\circ}C$와 $220^{\circ}C$에서 2, 4, 6시간, 증기처리는 $100^{\circ}C$에서 6, 24, 48시간 실시하였다. 잔류수지는 알콜-벤젠 용액으로 추출하였으며 휴대용 분광 색차계를 사용하여 재색을 측정하였다. 두께 20 mm 판재는 $150^{\circ}C$ 이상에서 2시간 열처리 또는 6시간 증기처리로, 두께 30 mm는 48시간 증기처리로 좋은 수지제거효과를 얻었다. 두께 30 mm 판재의 수지제거에는 처리시간이 가장 영향이 컸다. 판재 두께에 상관없이 백색도는 증기처리가 가장 높았으며 처리온도가 증가할수록, 처리시간이 길어질수록 감소하였는데 후자보다 전자에 더 영향을 받는다고 할 수 있다. 온도 $220^{\circ}C$에서 4시간 이상 열처리하더라도 백색도는 더 이상 변화하지 않았다. 온도 $220^{\circ}C$의 4시간과 6시간 열처리재는 재색이 분명하게 변하였으나 온도 $150^{\circ}C$의 열처리재는 12시간에서만 약하게 변하였다. 따라서 $150^{\circ}C$ 열처리로는 색상변화를 기대하기 어려울 것으로 생각된다. 열처리를 통해 표층뿐만 아니라 내층까지도 표층과 동일한 색상으로 변화시킬 수 있음이 증명되었다.

• 한국염색가공학회지
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• 제20권3호
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• pp.25-30
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• 2008

In order to examine the availability of a heating process for persimmon dyeing, the cotton fabrics treated with various concentrations of persimmon extracts were heated at various temperatures and times. The raw and fermented persimmon extracts were used for the coloration. For both extracts, the color strength of fabrics was. increased with the increase of coloration temperature, time, and concentration of the extracts. Considering the practical aspects. and color strength, the temperature around $200^{\curc}C$ and the time longer than 60 minutes can be determined as the. optimum coloration conditions of persimmon extracts onto cotton fabrics. However, somewhat loss of strength by the hearing process seems to be inevitable. The color fastness to washing was excellent for both color change and staining showing a rating of 5.

• 시스템엔지니어링학술지
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• 제12권1호
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• pp.113-120
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• 2016

Steel in a continuous reheat furnace is heated to higher temperature to be treated in the rolling steel process. Due to this reason the continuous reheat furnace system requires an optimal control system to adjust the temperature inside the furnace. Level 2 control systems for continuous reheat furnaces generate automatic heating set points for the level 1 system of the furnace based on the mathematical thermal model which can give a good estimation of steel heating inside the furnace and is used to adjust heating requirements to optimize furnace combustion. For the current study the analytic methodology based on the design procedure from the systems engineering to develop new level 2 control system of a continuous reheat furnace was proposed. The system analysis and the requirements of the level 2 control system were derived using the unified modeling language (UML) 2.0, and the design of database and the graphic user interface (GUI) for the level 2 control system were conducted.