• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.214.1-214
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• 2003

본 연구는 4~6개월의 유아들을 위하여 재수화시킨 후 숟가락으로 떠먹일 수 있도록 쌀을 기본으로 하고 당근, 쇠고기 및 계란을 각각 주재료로 한 냉동건조 이유식 제조의 최적조건을 결정하기 위하여 수행되었다. 본 연구에서 얻어진 결과를 요약하면 다음과 같다. 당근, 쇠고기 및 계란이유식에서 모두 냉동건조시간은 수분함량이 높고 가열판 온도가 낮을수록 증가하였다. 파쇄성은 수분함량이 감소하고 가열판온도가 증가함에 따라 증가하였다. 관능적 특성 중 수화속도, 균질성 및 매끄러운 정도는 수분함량이 증가하고 가열판 온도가 감소할수록 증가였고, 뜨기 쉬운 정도는 수분함량이 증가할수록 증가하였으나, 가열판온도의 영향은 거의 받지 않았다. 또한 피막형성성은 수분함량과 가열판온도가 증가할수록 증가하였다. 이유식 제조치 최적조건은 당근이유식의 경우 수분함량 88.5%와 가열한 온도 34$^{\circ}C$로, 쇠고기이유식에서는 수된함량 88.5% 와 가열판온도 28$^{\circ}C$로, 그리고 계란이유식에서는 수분함량 87.5%와 가열판 온도 39$^{\circ}C$로 결정되었다.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.680-689
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• 1995

Rice based infant foods of carrot, of beef, and of egg for 4-6 month old infants were prepared using freeze drying (FD) process. The optimum moisture content prior to FD and the plate temperature in the drier were determined with the use of response surface methodology. For all the infant foods under this study, FD time was longer as the initial moisture content was higher and the plate temperature was lower. Brittleness of the dried infant foods increased as the moisture content decreased and the plate temperature increased. Among the sensory attributes, hydration rate, uniformity, and smoothness were greater with increased moisture content and with decreased plate temperature. Ease to spoon increased as moisture content increased and mouthcoating increased as both the moisture content and the plate temperature increased. Optimum moisture content and plate temperature for the FD of carrot, beef and egg foods were 88.5% and $34^{\circ}C$, 88.5% and $28^{\circ}C$, and 87.3% and $39^{\circ}C$, respectively.

• Journal of the Korean Wood Science and Technology
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• v.30 no.2
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• pp.108-114
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• 2002

Red pine(Pinus densiflora) square timbers with 14.0 cm and 16.5 cm of face size and 24 m long were dried in a vacuum-press kiln and in a radio-frequency/vacuum(RF/V) kiln to compare drying rate, moisture content(MC) distribution and specific energy. RF/V drying rate was higher than vacuum-press drying rate. The effect of size of cross section on the RF/V drying rates were more pronounced than those of vacuum-press drying. The longitudinal- and the transverse MC distribution of dried square timber showed convex profile for the vacuum-press drying and concave profile for the RF/V drying. Moisture gradient of width direction was similar to the thickness direction in vacuum-press dried square timber and was more slight than that of the thickness direction in the RF/V dried large square timber. The specific energy consumption curve increased as MC decreased. Specific energy(kWh/kg of water evaporated) of the vacuum-press process required more than that of the RF/V process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.12
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• pp.3559-3566
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• 2009

Heating and cooling plate are separately used for heating and cooling cast dies for footwear parts. However, this has a disadvantage that it takes a long time to manufacture footwear parts etc.. In the present study, the pipe-inserted cast die for press forming process was proposed to substitute heating and cooling plate. The temperature distribution on the pipe-inserted cast die was analyzed by numerical work using a FEM. And its temperature was measured by LabView. A manufacturing by the pipe-inserted cast die for press forming process was effectively verified, especially in a productivity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.4
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• pp.853-858
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• 2008

The structures of induction heating type pressure rice cooker are consisted of oven. top heater plate and locking ring. Because the pressure is applied to their structures, those should be necessary to do the safety evaluation. In this paper, structure analysis is performed for oven structures by using finite element method and as a results, optimal thickness is achieved. Especially, analysis fur anisotropic layered material is performed because oven is made of both stainless steel and aluminum. And both von Mises and Tsai-Wu failure criterion are applied for safety factor. Parametric method is used in order to get the optimal thickness for oven and top heater plate.

• Journal of the Society of Naval Architects of Korea
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• v.39 no.2
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• pp.45-51
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• 2002

In Line Heating method, heating line is determined by kinematics analysis. But the heating line, which is solved by kinematics analysis, doesn't verify by the point of physical analysis and the choice problem in many heating line doesn't determine. In this paper, the simulator is developed. When we get the processing information at the kinematics analysis, simulator can estimate the shape of deformed plate that process along the processing information. When we get the initial shape and the object shape, we calculate the processing information first, using kinematics analysis. In a simulator, we estimate deformed shape from the processing information. After this we compare deformed shape and object shape. If the error of deformed shape and object shape is in the proper limits, that information is determined the final processing information. Else we repeat the process changing variables.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.799-804
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• 2002

Optimum conditions of freeze-dried carrots were determined using response surface methodology. Physicochemical and sensory properties of freeze-dried carrot prepared at different plate temperatures and chamber pressures were evaluated. Drying time increased with decreasing plate temperature and chamber pressure. Rehydration ratio decreased inversely with chamber pressure at low plate temperature, but increased proportionally with chamber pressure at high temperature. Density, color, and sensory off-flavor were not affected by the plate temperature and chamber pressure. Sensory color, tenderness, and carrot flavor increased with decreasing plate temperature, but were not affected by chamber pressure. Based on the drying time, rehydration ratio, and sensory attributes, optimum plate temperature and chamber pressure for the preparation of freeze-dried carrot were determined as $43^{\circ}C$ and 700 micronHg, respectively.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.115-115
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• 2010

고휘도 고효율 백색 LED (lighting emitting diode)가 차세대 조명광원으로 급부상하고 있다. 백색 LED를 생산하기 위한 공정에서 MOCVD (유기금속화학증착)장비를 이용한 에피웨이퍼공정은 에피층과 기판의 격자상수 차이와 열팽창계수차이로 인하여 생성되는 에피결함의 문제로 기판과 GaN 박막층 사이에 완충작용을 해줄 수 있는 버퍼층 (Buffer layer)을 만든다. 그 위에 InGaN/GaN MQW (Multi Quantum Well)공정을 하여 고휘도 고효율 백색 LED를 구현 할 수 있다. 이 공정에서 기판의 온도가 불균일해지면 wafer 파장 균일도가 나빠지므로 백색 LED의 yield가 떨어진다. 균일한 기판 온도를 갖기 위한 조건으로 기판과 induction heater의 간격, 가스의 흐름, 기판의 회전, 유도가열코일의 디자인 등이 장비의 설계 요소이다. 본 연구에서는 유도가열방식의 유도가열히터를 이용하여 기판과 히터의 간격에 차이에 따른 기판 균일도 측정했고, 회전에 의한 기판의 온도분포와 자기장분포의 실험적 결과를 상용화 유체역학 코드인 CFD-ACE+의 모델링 결과와 비교 했다. 또한 가스의 inlet위치에 따른 기판의 온도 균일도를 측정하였다. 본 연구에서 사용된 가열원은 유도가열히터 (Viewtong, VT-180C2)를 사용했고, 가열된 흑연판 표면의 온도를 2차원적으로 평가하기 위하여 적외선 열화상 카메라 (Fluke, Ti-10)를 이용하여 온도를 측정했다. 와전류에 의한 흑연판의 가열 현상을 누출 전계의 분포로 확인하기 위하여 Tektronix사의 A6302 probe와 TM502A amplifier를 사용했다. 흑연판 위에 1 cm2 간격으로 211곳에서 유도 전류를 측정했다. 유도전류는 벡터양이므로 $E{\theta}$를 측정했으며, 이때의 측정 방향은 흑연판의 원주방향이다. 또한 자기장에 의한 유도전류의 분포를 확인하기 위하여 KANETEC사의 TM-501을 이용하여 흑연판 중심으로부터 10 mm 간격으로 자기장을 측정 했다. 저항 가열 히터를 통하여 대류에 의한 온도 균일도를 평가한 결과 gap이 3 mm일때, 평균 온도 $166.5^{\circ}C$에서 불균일도 6.5%를 얻었으며, 회전에 의한 온도 균일도 측정 결과는 2.5 RPM일 때 평균온도 $163^{\circ}C$에서 5.5%의 불균일도를 확인했다. 또한 CFD-ACE+를 이용한 모델링 결과 자기장의 분포는 중심이 높은 분포를 나타냄을 확인했고, 기판의 온도분포는 중심으로부터 55 mm되는 곳에서 300 W/m3로 가장 높은 분포를 나타냈다. 가스 inlet 위치를 흑연판 중심으로 수직, 수평 방향으로 흘려주었을 때의 불균일도는 각각 10.5%, 8.0%로 수평 방향으로 가스를 흘려주었을 때 2.5% 온도 균일도 향상을 확인했다.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.79.2-79.2
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• 2005

• Journal of the Society of Naval Architects of Korea
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• v.38 no.4
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• pp.66-74
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• 2001

Plate bending process is indispensible in shipbuilding. The process includes press bending process and heating process. Especially the heating process is carried out exclusively by skillful workers. Many researches have been made to automate the heating process. This study was carried out as a fundamental study to develop a efficient analysis method for triangle heating and focused on clarifying the deformation characteristics of plate by triangle heating and essential elements effect on the deformation. In this paper, we proposed an analysis model for thermal-elastic-plastic analysis and simulated the deformation by triangle heating using ANSYS based on the experimental results of Jang et al.(2001). Also, we showed the deformation characteristics more clearly by comparing the deformation due to triangle heating and line heating in case that the total heat input is same. Finally, we investigated the change characteristics of deformation elements according to the volumetric heat input.