• Korea-Australia Rheology Journal
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• 제21권2호
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• pp.83-89
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• 2009

Coating process plays an important role in information technology such as display, battery, chip manufacturing and so on. However, due to complexity of coating material and fast deformation of the coating flow, the process is hard to control and it is difficult to maintain the desired quality of the products. Moreover, it is hard to measure the coating process because of severe processing conditions such as high drying temperature, high deformation coating flow, and sensitivity to the processing variables etc. In this article, the coating process is to be re-illuminated from the rheological perspectives. The practical approach to analyze and quantify the coating process is discussed with respect to coating materials, coating flow and drying process. The ideas on the rheology control of coating materials, pressure and wet thickness control in patch coating process, and stress measurement during drying process will be discussed.

• 한국결정성장학회지
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• 제11권3호
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• pp.120-126
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• 2001

세라믹 제품의 건조공정을 해석 할 수 있는 시뮬레이션 시스템을 개발하였다. 해석 시스템은 전처리 프로세서, 해석 모듈, 후처리 프로세서로 구성되어 있다. 전처리 프로세서에서는 세라믹 제품을 3차원으로 모델링하고 유한요소 메쉬를 생성하며, 해석 모듈의 입력 데이터를 만드는 과정을 수행한다. 해석 모듈에서는 유한요소 메쉬의 절점과 요소에 관한 정보, 물성치, 경계조건을 이용하여 건조공정중의 온도, 습도, 응력, 변형률 등을 해석한다. 그리고 후처리기에서는 설계자가 해석결과를 쉽게 이해할 수 있도록 해석결과 데이터를 가시화 해준다.

• Carbon letters
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• 제14권3호
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• pp.193-195
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• 2013

Expanded graphite (EG) was prepared using a drying process for application as an oil-adsorbent: the morphology, expansion volume, and oil absorption capacity of the EG were investigated. The expanded volume of the EG increased with an increasing reaction time and heat treatment temperature. The oil adsorption capacity of the EG was 45 g of n-dodecane per 1 g of EG. It is noted that the drying process of EG is a useful technique for a new oil-adsorbent.

• 수산해양교육연구
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• 제20권3호
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• pp.508-519
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• 2008

Hot air drying is a method that let moistures evaporate by heat exchange between heating air and dry target. This way is dominating more than about 70% of dryers that the use extent is wide fairly, and is established in domestic than dryer that use conduction or radiation etc. Most of research about drying had been emphasized in size of device through analysis for these dry phenomenon plain, heating topology, and aspect of form and so on by dry target's special quality, and research about device development or waste heat withdrawal technology in energy utilization efficiency side is slight real condition. Therefore, in this study, Investigated numerically about thermal efficiency elevation that is leaned against as that change the temperature of inlet and outlet in heat exchanger of the hot air drying tower.

• 한국연초학회지
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• 제25권1호
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• pp.34-38
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• 2003

This study was carried out to investigate the changes of dehydration process and quality of cured leaves with crushed midribs and cut of the yellowed leaves during drying stage of flue-cured tobacco. The crushed midribs of yellowed leaf dried out before raising the highest temperature of midrib drying stage and reduced the curing time by about 20 hours. However, the cut of yellowed leaf was not affected the curing time and dehydration process during drying stage of flue-curing due to a problem with the cut leaves packing excessively in the curing container. The cured weight yield was increased with crushed midrib and cut leaves, and nicotine and sugar contents of cured leaves and quality in terms of dollars per kilogram were decreased with crushed midrib and cut leaves.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.287-288
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• 2006

Two approaches for the fabrication of tailored powder composites with specially distributed pore-grain structure and chemical composition are investigated. Electrophoretic Deposition (EPD) followed by microwave sintering is employed to obtain functionally graded materials (FGM) by in-situ controlling the deposition bath suspension composition. $Al_2O_3/ZrO_2$ and zeolite FGM are successfully synthesized using this technique. In order to fabricate an aligned porous structure, unidirectional freezing followed by freeze drying and sintering is employed. By controlling the temperature gradient during freezing of powder slurry, a unidirectional ice-ceramic structure is obtained. The frozen specimen is then subjected to freeze drying to sublimate the ice. The obtained capillary-porous ceramic specimen is consolidated by sintering. The sintering of the graded structure is modeled by the continuum theory of sintering.

• 한국식품과학회지
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• 제25권5호
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• pp.558-564
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• 1993

쌀보리를 시료로 하여 건조조건을 다르게 하여 유동층 건조특성에 영향을 미치는 외부요인에 대해서 조사한 결과를 요약하면 다음과 같다. 쌀보리의 유동층건조는 항률건조기가 없이 감률건조 1단계, 감률건조 2단계의 두 단계로 일어남을 알 수 있었다. 또한 건조속도상수는 충전량이 적을수록, 공기속도가 클수록, 공기온도가 높을수록, 상대습도가 낮을수록 켰으며, 감율건조단계에서의 건조속도상수는 Arrhenius형의 plot에서 좋은 직선관계를 나타내어 이 단계가 활성화 과정임을 알 수 있으며, 감률건조 제 1단계의 활성화 에너지는 1900ca1/gmol, 감률건조 제 2단계의 활성화 에너지는 2500ca1/gmol을 각각 나타내었다.

• 한국식품과학회지
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• 제21권2호
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• pp.212-217
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• 1989

무우 및 고구마를 열풍건조하고 건조가 진행됨에 따라 표면적 변화를 측정하여 실험치와 잘 일치하는 건조수축식과 총괄적 건조 속도식을 구하였으며, 시료의 두께, 상대습도 및 풍속을 포함한 초기 건조속도의 함수관계 식을 구하였다. 건조속도 상수와 차수는 시료의 두께와 공기의 온도에 영향을 받았으며 일정한 건조 (d=4mm, $Ta=50^{\circ}C$, RH=10%, U=0.8m/s) 하에서 얻어진 총괄적 건조속도 식과 수축식은 무우는 $dx/dt=0.112{\times}10^{-2}{\cdot}A{\cdot}:(1-x)^{0.43}$, A=Ao(-0.480x+1)이었고, 고구마는 $dx/dt=0.115{\times}10^{-2}\;A(1-x)^{0.49}$, A=Ao(-0.368x+1)이었다. 또한 초기 건조속도의 변화는 시료의 두께, 상대습도, 및 풍속에 대해 무우는 $dx/dt=0.0648\;(RH)^{-0.31}\;(d)^{-0.75}\;(U)^{0.39}$이었고, 고구마는 $dx/dt=0.0547(RH)^{-0.28}\;(d)^{-0.63}\;(U)^{0.37}$이었다.

• 한국식품영양과학회지
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• 제20권5호
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• pp.503-508
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• 1991

영암어란의 제조방버은 건조기간이 긴 자연건조법으로 제조조건에 따라서 품질이 다르고 저장중 산화, 변색 및 단백질의 열화가 일어나 품질이 저하하였다. 본연구는 좋은 품질의 영암어란을 제조하기 위한 조건들의 확립을 위하여 품속에 따른 구성아미노산 함량과 산가, 과산화물가, TBA가의 변화로 최적풍속을 찾고 특성곡선을 구하였다. 엄장농도 5%, 바르는 참기름량은 3.0g/day에서 양호한 품질을 유지하기 위한 최적풍속으로 60% RH와 $20^{\circ}C$에서 2m/sec로 확정하였다. 영암어란의 제조에서 전통건조 방법의 건조기간은 20일이었으나 본 실험의 2m/sec 풍속에서 7일로 단축되었으며 이때의 건조특성곡선은 항율건조기가 없었고 감율건조기만 있었다.

• 한국안전학회지
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• 제34권4호
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• pp.32-40
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• 2019

During the manufacturing process of a printed circuit board(PCB), fumes and mists are generated as the ink dries on the PCB surface. The generated fumes and mists are deposited in the dryer wall and the exhaust duct. Deposited fumes and mists may present a fire hazard if the dryer temperature control system fails. In this study, the thermal stability of the fumes and mists deposited in the dryer and ducts has been analyzed by experimental methods such as thermo gravimetric analysis (TGA), differential scanning calorimetry (DSC), auto ignition temperature (AIT), and multiple mode calorimetry(MMC). According to the experimental analyses, experimental samples are likely to generate gas at the temperature ($180{\sim}240^{\circ}C$) that deviates from the normal operating temperature ($150{\sim}156^{\circ}C$). It has been shown that the thermal stability is degraded when the temperature is deviated from the normal operating temperature. In the end, engineering and management safety measures of accidental prevention have been suggested.