• Journal of the Korean Wood Science and Technology
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• 제32권4호
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• pp.46-51
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• 2004

본 연구에서는 국산 리기다소나무의 대량 수요 창출과 이용기술 개발, 특히 구조용집성재 라미나로서의 이용 가능성 구명을 위해 고온에서 건조된 판재의 변형량과 변색정도를 조사 평가하였다. 함수율 분포시험을 통해 평가된 고온건조판재 내 적은 함수율 경사, 프롱테스트를 통해 확인된 적은 내부 잔류응력, 집성가공 가능한 적은 변형량 등은 본 연구에서 적용된 고온건조스케쥴이 구조용집성재용 라미나 건조조건으로 사용 가능성이 높다는 결과를 보여주었다. 예비실험을 통해 송진에 의한 접착장애는 발생하지 않는 것으로 확인 되었으나, 잔류수지에 의한 구조용집성재의 접착내구성 및 도장성능 감소현상 구명을 위한 수지정량 분석시험이 추후 요구되었다. 또한 최종 함수율이 집성재 라미나로서 이용 가능한 함수율보다 상당히 낮은 수준으로 건조되었으며 저온열기건조 판재에 비해 변색이 심하므로 함수율 제어 및 변색 억제를 위한 최적의 건조조건 구명에 대한 연구가 좀더 필요할 것으로 사료된다.

• 한국의류학회지
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• 제34권12호
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• pp.2062-2072
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• 2010

This research evaluates the change of the water absorbency and drying speed of a quick-drying knit fabric by repeated laundering and laundering conditions and investigates the influence of laundering conditions on the functional properties of the knit fabric. Four factors of laundering conditions were studied: detergent, water hardness, water temperature, and frequency of rotation. Knit fabrics were washed for 25 laundering cycles in a drum-type washing machine with nine different laundering conditions derived from an orthogonal array. The properties of knit fabrics were measured with a drop absorption test, a strip test, and a drying time test. Relaxation shrinkage pointed to a change in the structural characteristics of the knit fabric. Wetting time was faster and wickability was greater in the knit fabrics that underwent 5 laundering cycles; in addition, there were no obvious changes in wetting time and wickability. The detergent was the most important factor in wetting time (40.4%) and wickability (60% or above). Water hardness, water temperature and RPM had less of an effect on wetting time and wickability. There were no significant differences between the levels of laundering conditions (except for detergent) on wetting time and wickability. Drying times with neutral and alkali were slower by repeated laundering; however, there was no obvious change in drying time. Hardness, water temperature and RPM had less of an impact on drying time.

• 한국응용과학기술학회지
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• 제33권1호
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• pp.58-66
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• 2016

저온진공건조 조건에 따른 곶감의 건조특성 및 품질적 변화를 분석하였다. 곶감의 건조 특성은 전형적인 항율건조기간과 감율건조기간이 존재함을 확인 할 수 있었다. 진공압력이 높을수록 가열온도가 높을수록 곶감의 당도, 당 함량, 경도 값은 높게 나타났으며 이에 비해 명도 값은 낮게 나타남을 알 수 있었다. 기존 천일 및 열풍건조를 대처할 수 있는 진공건조의 최적 조건은 진공압력이 40~50kPa abs., 가열온도 $30^{\circ}C$, 건조시간은 3~4일 이었다.

• Journal of the Korean Wood Science and Technology
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• 제22권1호
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• pp.12-19
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• 1994

An electrically heated experimental lumber dry kiln was retrofitted with a computer-based control system to control kiln conditions more precisely and monitor and record several kiln variables. Flat-sawn 2.5cm-thick Pinus densiflora boards were dried in constant temperature process(65$^{\circ}C$ & 50~60 %RH) and continuously rising temperature process, respectively. The average drying rate in continuously rising temperature process was 5.7 %/hr, which was above 3 times faster than that in constant temperature process. But, the average rate of case-hardening and moisture difference between shells and cores of boards dried in continuously rising temperature process were 82 % and 5.5 %, respectively, which were much larger than those of boards dried in constant temperature process.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.396-404
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• 2000

Post harvest processes for rice include drying, storage and processing. Drying has a great effect on the quality of the grain. The existing rice centers are with the ill equipped, especially with drying and storage facilities. The rice harvesting has bully mechanized, a large volume of rice with high moisture content are taken to the rice processing complex(RPC). Three, the need for drying and storage facilities becomes more urgent. At present the daily drying capacity of RPC can't exceed over 40~50 M/T. Therefore new technology and facilities for a high quality and main efficient drying should be introduced one such technology is the continuous flow drying system. This research, aims to test performance efficiency the mixed continuous flow grain dryer was whose daily drying capacity is 100 M/T. The results of the performance tests of the dryer are shown as follows; (1) The temperature distribution of the drying modules were measured by a temperature recorder. The fifth module showed the highest value, followed by the seventh and the third. (2) When the intake air temperature was $55^{circ}C$, the drying rates were 1.7 and 2.6%, wb/pass in the exhaust temperatures of 20 and $22^{circ}C$. And when the intake air temperature was $60^{circ}C$, the drying rates were 1.7 and 2.3%, wb/pass in the exhaust temperatures of 22 and $25^{circ}C$. (3) The average increased rate of cracked grains after the drying process was 0.7% which is below the tolerance limit (2.0%) of the continuous grain dryer.

• 한국식품과학회지
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• 제21권1호
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• pp.145-148
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• 1989

건조표고버섯의 품질을 향상시키기 위해 열풍, 원적외선 및 냉동 건조시 건조조건이 품질에 미치는 영향에 대해 조사하였다. $45-70^{\circ}C$ 범위에서 열풍건조시 온도가 증가할수록 부피유지율은 높았으나 복수율은 낮았으며 5'-GMP 함량은 $50^{\circ}C$에서 건조한 것이 가장 많았다. 원적외선 전조는 같은 온도에서의 열풍건조에 비해 복수율은 높았으나 부피유지율이 낮았다. 냉동건조시 냉동속도에 따른 부피유지율의 차이는 뚜렷하지 않았지만 복수율은 $-18^{\circ}C$에서 냉동시킨 것이 가장 높았으며 건조속도에 의한 영향은 건조속도가 빠를수록 복수율이 증가하였다. 또한 냉동속도와 건조속도가 빠를수록 5'-AMP, 5'-GMP 와 5'-XMP 함량이 모두 증가하는 경향이었다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.1128-1133
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• 2008

Drying process in the thin film layer of sludge with the thickness less than a few millimeters has been investigated using the simple one-dimensional model. Thin film drying is usually used to dry the viscous materials like sewage sludge. The thin film layer of sludge is dried on the metallic surface through which thermal energy is supplied to the layer during drying. In order to solve the equations, the mass transfer rate on the drying surface should be determined. The mass flux of evaporated water vapor on the surface is estimated with the formulation given in the literature. The effect of heating temperature, film thickness, and air velocity on drying has been examined to figure out the drying characteristics of the sludge layer.

• 한국식품영양과학회지
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• 제18권1호
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• pp.29-33
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• 1989

본 연구는 마이크로컴퓨터를 활용하여 식품건조 공정중 온도, 무게 변화에 대한 자료수집과 온도를 자동제어 하기위해 접속장치, 온도와 무게 계측장치, 온도제어시스템을 설계제작하였다. 또한 이들 시스템을 운영하기 위해 basic언어 Assembly언어로 프로그램을 작성하여 수행한 결과 건조중 식품무게변화와 온도변화값을 성공적으로 계측할 수 있었고 건조온도를 설정된 목표값에 따라 자동제어가 가능했다.

• Journal of Biosystems Engineering
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• 제32권1호
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• pp.6-12
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• 2007

This study was conducted to investigate the drying characteristics of oak mushroom using stationary far-infrared dryer. Drying characteristics was measured at drying air velocity 0.4 to 0.6 m/s and drying temperature 50, 60, and 70$^{\circ}C$, respectively. With high temperature of far-infrared heater and fast air velocity, the far-infrared drying rate of double air flow system was better than conventional heated-air drying as much as 39%. The value of color difference (E) of oak mushroom before and after drying was 8.95 by using heated air drying and was in the range of 3.76$\sim$6.98 by the far-infrared drying. The shrinkage rate of oak mushroom after heated air drying was higher than that of air velocity, 0.6 m/s of far-infrared drying conditions, and was lower than that of air velocity, 0.4 m/s of far-infrared drying conditions. The content of free amino acid was higher in far-infrared drying than heated air drying.

• Journal of Biosystems Engineering
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• 제34권1호
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• pp.30-36
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• 2009

This study was performed to determine the effect of drying conditions on the germination properties of rapeseed after seeds were dried under different drying conditions: $40^{\circ}C$, $50^{\circ}C$, or $60^{\circ}C$ in combination with 30%, 45%, or 60% relative humidity. As analytic results, drying conditions had significant effects (P-value < 0.001) and drying temperature was considered as the main factor on the germination properties of rapeseed. When drying temperature increased or relative humidity decreased, the vigor rate and germination rate decreased, the median germination time increased. The maximum values of vigor rate and germination rate were 90% and 95.44%, and their minimum values were 60.17 and 75%, respectively. To ensure the standard germination rate of 85%. The appropriate drying zone was determined and the drying temperature should be less than $51.0^{\circ}C$, $54.5^{\circ}C$ and $58.7^{\circ}C$ at 30%, 45% and 60% RH, respectively. The values for median germination time varied from 2 to 4 days. The predicted models of germination rate, vigor rate, and median germination time were determined.