• 한국정밀공학회지
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• 제9권4호
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• pp.109-117
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• 1992

Mixing of ceramic-binder system was investigated experimentally and theoretically for application to Ceramic Injection Molding. Polypropylene, stearic acid, and paraffin wax were selected as the binder system, and silicon nitride fine powders were selected as the ceramic material. Single screw ectruder was employed as the mixing equipment. Theoretical analysis was performed to investigate the mixedness of mixture quantitatively. The analysis predicted average residence time average total strain, and average shear stress as a function of screw speed for mixtures of different volume fraction. Qualitative mixedness of mixture and characteristics of mixing were investigated by using SEM and EPMA. In addition, rheological properties of the mixture were investigated by using a capillary rheometer to examine possibility of injection molding.

• 한국식품조리과학회지
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• 제14권3호
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• pp.241-249
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• 1998

The purpose of this study was to develop a recipe for high quality Yackwa (fried cake made of wheat flour) by adjusting the mixing ratio of flours, frying temperature and time. Yackwas were prepared by using 3 kinds of flour mix (3：7, 4：6, and 2：8 of weak to medium ratio), fried at various temperatures and times, and evaluated by mechanical characteristics and sensory evaluation. It was found that Yackwa prepared with 3：7 mixing ratio of flour and fried at 160$^{\circ}C$ for 9 min was most preferred. Yackwas with the same flour mixing ratio and fried at 150-155$^{\circ}C$ for 12∼16 min were also within the range of acceptance. The characteristics of desirable Yackwa were suggested to be soft, crispy, and to have little taste of oil.

• 상하수도학회지
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• 제21권3호
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• pp.273-278
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• 2007

Modern society has moved from a phosphorus recycling loop, where animal manure and human wastes were spread on farming land to recycle nutrients, to a once-through system, where phosphates are extracted from mined, non-renewable phosphate rock and end up either in landfill(sewage sludge, incinerator ash) or in surface waters. In this research, crystallization of nitrogen and phosphate with natural sources of $Mg^{2+}$ in synthetic water was tested. The operational parameters of pH, mixing time, and the magnesium molar ratio were investigated to find optimal conditions of the MAP precipitation using synthetic wastewater. The removal efficiency of phosphate increased with pH up to 11. By MAP precipitaiton of the synthetic waste water, 94% of the phosphate were eliminated at pH 11. It was found that at least 10 minutes mixing time was required and 20 minutes mixing time was recommended for efficient phosphate removal. High efficiency removal of phosphate was possible when the magnesium molar ratio was 1.0~2.0. The comparative study of different magnesium sources showed that coagulants (PAC) was the more efficient sources than only magnesium. The result showed that 97% of phosphate removal. In conclusion, coagulants (PAC) induced crystallization of struvite and hydroxyapatite was shown to be a technically viable process that could prove cost effective for removing phosphate in wastewater.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.232-237
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• 2005

The cellulloytic enzymes, such as FPase and amylase, production by Trichoderma inhamatum KSJ1 using 10L air circulation bioreactor were tried. Physical properties of the employed bioreactor, mixing time, $k_{L}$ a were examined in airflow conditions of enzyme production cultures. Mixing time of distilled water at 0.6, 1.2, 1.8 vvm were 25, 21, 9 sec, respectively, and mandel's medium using rice straw and pulp as carbon sources were 31, 25, 15 sec. Mixing time decreased when airflow rate increased. $k_L$ a of distilled water at 0.6, 1.2, 1.8 vvm were measured -22.52, -29.31, -39.62, respectively, and the mandel's medium were -47.8, -18.5, -21.4. The $k_L$ a values was increased linearly as the air-flow rates increased. However the values in mandel's medium showed different results, especially at 0.6 vvm. Amylase and FPase activity at the 1.2 vvm was 3.39U/mL, 0.72U/mL in 5 days cultivation. and the activities at 0.6 vvm were 2.01U/mL, 0.39U/mL, respectively. The enzyme productivity at 1.2 vvm was higher than at 0.6 vvm, indicating that high oxygen tension is requested for the efficient enzyme production culture of T. inhamatum KSJ1.

• 한국작물학회지
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• 제47권1호
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• pp.1-12
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• 2002

Flour characteristics of Korean winter wheat grown in Suwon in 1997 and 1998, and in Suwon and Deokso in 1998 were evaluated. Korean winter wheat cultivars were significantly influenced by years and locations in flour properties such as ash content, protein content, damaged starch content, starch swelling volume and power. Protein content was highly correlated with starch damage and alkaline water retention capacity. There were highly significant correlations between mixing time of mixograph and SDS sedimentation volume. Swelling properties of flour and starch were highly correlated with pasting properties of flour and starch, respectively. Compared to commercial flours for baking, Alchanmil, Gobunmil, Keumkangmil and Tapdongmil showed similar protein content, SOS sedimentation volume and mixograph mixing time. Eunpamil, Geurumil, Olgeurumil, Suwon 258, Suwon 261, Suwon 265, Suwon 275, Suwon 276, Suwon 277, Suwon 278 and Urimil had similar values to commercial noodle flours in SDS sedimentation volume. Alchanmil, Olgeurumil, Suwon 274, Suwon 275, Suwon 276 and Urimil showed higher swelling and pasting properties than the others. Chokwang, Olgeurumil, Suwon 277 and Urimil were similar to commercial cookie flours. Friabilin-absence lines showed higher protein content and starch damage than those of friabilin-presence lines. Absence lines of 1D$\times$2.2 + 1Dy12 subunit in high molecular weight glutenin subunits showed higher SDS sedimentation volume and mixing time of mixograph than those of presence lines.

• 한국해안해양공학회지
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• 제12권4호
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• pp.190-194
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• 2000

선형파 이론에서 제시되는 유속분포를 이용하여 파랑인자에 의하여 영향을 받는 분산계수를 이론적으로 유도하였다. 유도된 분산계수는 수심평균, 주기 평균된 값으로 천해조건보다 심해조건에서 큰 값을 보이고 있다. 또한, 분산계수 값은 연직 방향 혼합시간에 비하여 큰 주기 값에서는 특정한 값으로 수렴하고, 매우 작은 주기 값에서는 0으로 되는 일반적인 경향도 보이고 있다. 한편, 단순한 지형 및 가정 하에서 유도된 본 분산계수를 보다 실질적인 상황에서도 적용할 수 있고, 천해영역의 조건을 반영할 수 있도록 보완·수정할 필요가 있다.

• 동아시아식생활학회지
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• 제17권6호
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• pp.883-893
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• 2007

To optimize the preparation process for oven-roasted glutinous rice cake, an experiment was derived using a central mixing composite design to determine the optimal conditions. The addition of flour by soaking time as well as sucrose and water, were the independent variables, with the moisture content, color, sensory, and texture properties of the ovenroasted glutinous rice cakes selected as response variables. For the moisture content, color, sensory, and textural properties, we found significant effects for moisture, lightness, redness, hardness, and cohesiveness in the oven-roasted glutinous rice cakes, and water was one of the most influential factors. The optimal mixing conditions for the highest quality oven-roasted glutinous rice cake, in terms of sensory and textural properties, were 266.0 g of water, 25.4 g of sucrose, and 61.5 minutes of soaking time for the glutinous rice flour. The soaking time was in close to the median, whereas the water and sucrose values were slightly above the median.

• 대한화장품학회지
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• 제21권2호
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• pp.112-128
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• 1995

화장품 폐수에 일정 농도의 오수를 혼합하여 활성 슬러지법에 의해 처리할 경우, 오수 중의 각종 영양원과 분변성 세균 등에 의해 폐수 중 유기물이 감소되는지의 여부를 COD를 측정하여 고찰해 보고 폐수와 오수의 혼합 시 안정적으로 처리될 수 있는 최적 혼합비와 최적 폭기 시간을 구한 결과, 적당량의 오수를 투입함으로써 폐수 처리에 필요한 폭기 시간을 4-8시간으로 단축시킬 수 있었다. 오수의 투입량이 증가될수록 COD 저감율이 커짐을 알 수 있었으며 본 실험 범위 안에서 폐수와 오수의 혼합 처리 시 오수의 함량이 80% 정도일 때 가장 효과적이었다.

• 한국전자통신학회논문지
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• 제14권1호
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• pp.191-198
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• 2019

본 논문에서는 주유소에서 초보운전자들이나 박혀있는 고정관념으로 인해 발생하는 혼유 사고를 방지하는 것을 구현하였다. MQ-9 가스 센서를 이용하여 차량 연료용 탱크의 CO 가스 농도를 측정한 후 경유와 휘발유를 감별하여 주유기의 유종과 다를 경우 서보모터를 이용하여 주유기 노즐의 손잡이를 잠가 혼유를 방지할 수 있는 주유기의 혼유 방지 장치에 관한 것이다. 또한 주유를 마치고 세차를 하려는 이용 고객의 시간 절약과 편의성 도모를 하기 위한 세차 시간 표시를 적외선 센서를 이용하여 구현하였다.

• Macromolecular Research
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• 제9권1호
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• pp.37-44
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• 2001

A premixing effect for the properties of carbon black-filled rubber compounds was investigated using biblends of natural rubber (NR), styrene-butadiene rubber (SBR), and butadiene rubber (BR). Degree of mixing of the biblends was controlled by preblending time of 0.0, 2.5, and 5.0 min. Mooney viscosities of the compounds decreased by increasing the preblending time. Of three carbon black-filled compounds of NR/SBR, NR/BR, and SBR/BR compounds, only the SBR/BR blends showed a specific cure characteristics depending on the preblending time. For the bound rubber composition, the NR content was higher than SBR and BR. The difference in the rubber composition ratio of the bound rubber became smaller with increasing the preblending time. Physical properties of the vulcanizates such as hardness, modulus, tensile property, abrasion loss, and tans were also compared. Differences in properties of the compounds were discussed with miscibility of the dissimilar rubbers and degree of mixing.