• 한국농공학회지
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• 제16권1호
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• pp.3263-3291
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• 1974

Experimental work of grain bin was carried out to develop the methods of natural air in-bin drying and storage. The method is considered to be more economical, labour saving, and an effective countermeasure to grain loss. To examine the possibility of farm use of the grain bin and to analyze the related factors concerned with in-bin grain drying and storage, ambient air conditions (especially the change of air temperature and relative humidity) and grain quality during drying and storage periods were investigated. A laboratory model bin was constructed to investigate the effect of different forced air conditions on the drying characteristics of rice. In addition, a grain bin with 2.2m diameter and 1.8m height, considered to be the optimum size for the average Korean farm, was constructed and tested to examine the drying and storing characteristics of rice. The weather data analyzed in this study was the nine-year (from 1964 to 1972) record of air temperature and relative humidity in the Suweon area, and the thirty-year (from 1931 to 1960) record of pentad normal relative humidity and air temperature in the Seoul area. From the results of the weather data analyses, the adequate air delivery hours (which was arbitrary defined as the condition to give less than 75% relative humidity) to dry the rice during October were about nine hours (from approximately 10 A.M. to 7 P.M, ) a day, in which the average air temperature was about 15.9$^{\circ}C$ and average relative humidity was 66%. The occurence of days having three hours of such conditions was 1, 2, and 1-day within the 1st, 2nd add last 10-day periods for the month of October, respectively. Therefore, it may be considered that the weather condition in October was satisfactory for the forced natural air drying. The results of the laboratory model bin test were analyzed to obtain the drying curve and drying rate for different drying stages and grain layers in the bin corresponding to various conditions of forced natural air. A drying experiment with a prototype grain bin showed that an approximate 5 percent grain moisture gradient through a 1.6 meter grain deposit was observed after 80 hours of intermittent drying, giving an over dried zone in the lower grain layers and an extremely high grain moisture zone in the upper layers. This indicates that an effective measure should be taken to reduce this high moisture gradient. In order to investigate the drying characteristics of bulk grain in a layerturning operation a grain bin test was performed. This showed a significant improvement of uniform drying. In this test, approximate 107 hours were required to dry a depth of 1.6 meter of grain from an initial moisture content of 22.2 percent to a moisture content of 16.7 percent using an air delivery rate of 2.8 cubic meter per a minute per every cubic meter of grain. This resulted in a 2 percent moisture gradient from the top to the bottom of the bin. During storage period, till the end of June the average temperature of grain was 2~3$^{\circ}C$ higher than ambient air temperature. But during July when the grain moisture content went up slightly (less than 1 percent), the average temperature of the grain also increased to 3~5$^{\circ}C$ higher than ambient air temperature. It is therefore recommended that for safe grain storage, grain should not be stored in sheet metal bins after mid May. From the above results, in-bin rice drying and storage can be used effectively on Korean farms. It is strongly recommended that the use of grain-bin system should be implemented for farm use to improve farm drying and storage of rice.

• 한국축산식품학회지
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• 제35권5호
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• pp.597-603
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• 2015

The purpose of this study was to investigate the influence of processing conditions (temperature and time) and binding agent types (glutinous rice flour, potato starch, bean flour, and acorn flour) on the physicochemical and sensory characteristics of ground dried-pork meat product. For this purpose, ground dried-pork meat product was produced by adding several binding agents at different drying temperatures and times. The drying time affected moisture content and water activity in all drying temperature. However, under the similar drying conditions, the extent of drying varied depending on the type of binding agents. The results of sensory evaluation for texture degree and overall acceptability indicated the following: overall, higher drying temperatures and longer drying time heightened the degree of texture, and the overall acceptability varied depending on binding agent type. Physicochemical and sensory characteristics were analyzed to determine any possible correlation. The results revealed a high correlation between moisture content, water activity, shear forces, and sensory evaluation (p<0.01). However, there was no correlation with respect to overall acceptability.

• 한국태양에너지학회 논문집
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• 제35권1호
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• pp.29-34
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• 2015

The photovoltaic ribbon attached the flux reduces the solar module manufacturing process and the pollution. This paper presents an analytical method for solving the continuous flux drying system of photovoltaic ribbon. Also, some experiments of the drying of photovoltaic ribbon are carried out in order to design the drying system. Numerical results indicate the air temperature, the air velocity, the air pressure and the timewise temperature variation of ribbon during drying process. In case of the drier process length is short, 400mm, the photovoltaic ribbon is wet. Thus, another study of drying system is necessary to improve the drying ability. As a result, multi-stage drier system is proposed and shown to be good drying ability.

• Journal of Biosystems Engineering
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• 제21권1호
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• pp.72-83
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• 1996

This study was performed to find out drying characteristics and develop drying model for the design of an efficient dryer or drying system of garlic. The basic model which describes drying phenomenon of garlic was first established. A series of drying test were conducted with two varieties of garlic(Uiseong, Namdo) at 9-different drying conditions (drying temperatures ; $40^{\circ}C$, $50^{\circ}C$, $60^{\circ}C$, relative humidities ; 20%, 35%, 50%) and statistical analysis was made to fit the data with exponential equation, approximated diffusion equation, page equation, thompson equation and wang equation, respectively. In this test, the effects of drying air temperature and relative humidity on the drying rate were undertaken. Finally, new drying model based on these experimental results was developed to describe the drying characteristics of garlic. Also, the volatile components of garlic extracts were investigated. For experiment both Uisoeng and Namdo garlic were dried by heated-air-drying, followed by ether extraction. The extracts were analysed by Gas chromatography/Mass spectrometer.

• 한국전산유체공학회지
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• 제16권2호
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• pp.75-80
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• 2011

In this study, three-dimensional transient numerical simulations were carried out for a paint drying system of vehicle. The vehicle on assembly line passes through the drying system consisting of hot and cool air blow region. For the moving motion of the vehicle, moving of inlet boundary condition and MRF technique are used. The transient distribution of temperature and velocity in the drying system were predicted numerically. In order to validate the numerical results, transient distribution of the vehicle surface temperature was compared with experimental data, showing a good agreement. As a result of present study, optimal operating condition of the drying system are to be suggested.

• 한국식품저장유통학회지
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• 제8권2호
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• pp.140-145
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• 2001

Although the drying times of paddies were significantly shortened by the application of higher drying temperatures, the 12, 10 and 8 hours were needed for the reduction of moisture contents from 23.55 to 15% at the temperatures of 45, 50 and 55$\^{C}$, respectively. Milling yields(MY) and rice rates(HRR) were decreased by increasing of the drying temperature. The MY ratios were 75.50, 75.42 and 75.31% and HRR were 93.28, 92.14 and 91.12% in drying temperature of 40, 50 and 55$\^{C}$, respectively. In the milling processes of tough rice with the used of a milling machine equipped with both of abrasive and friction types in a body, the reduction rates of bran and the occurrence of broken rice increased with the pressures at outlet or the recycled passing tines. In the process for humidified friction whitening of rice, it was found that the optimum addition rate of water for the best quality was the 11.2 liters per tone of white rice.

• 한국식품영양과학회지
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• 제25권5호
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• pp.774-778
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• 1996

건조온도(40, 50 and $60^{\circ}C),$ 저장온도(4 and $20^{\circ}C)$ 및 저장기간(0,1,2,4months)에 따른 홍합과 바지락의 유기산 함량의 변화는 다음과 같았다. 두 시료 모두 8종의 유기산을 분석하였으며, 홍합에서는 succinic acid의 함량이 410.9mg%로 전체 유기산의 90% 이상을 차지하였으며, malic acid가 41.2, pyroglutamic acid가 11.6, lactic acid가 11.4mg%의 순으로 많았으며, 바지락에서는 succinic acid가 96.5mg%로 가장 많았으며 lactic acid가 61.9, pyroglutamic acid가 59.8, malic acid가 21.7mg%로 많았다. 건조에 의하여 유기산의 함량이 전체적으로 감소하였으며 건조온도가 높을수록 함량 감소가 더 크게 나타났다. 그리고 저장온도가 높을수록, 저장기간이 길수록 함량 감소율이 더 크게 나타났다.

• 한국식품영양과학회지
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• 제25권5호
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• pp.768-773
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• 1996

건조온도, 저장온도 및 저장기간에 따른 홍합 및 바지락의 아미노산 함량 변화는 다음과 같다. 생시료의 경우 총 아미노산의 함량은 두시료 모두 6575.30mg% 와 6764.43mg%로 비슷하게 나타났으며, 건조에 의한 함량의 감소는 홍합 보다 바지락의 경우가 더 많이 감소하였다. 아미노산 함량은 두시료 모두 Glx가 790.55 및 990.89mg%로 가장 많았으며 , 기타 아미노산의 함량은 시료에 따라 조금씩 달랐다. 시료를 건조함에 따라 아미노산의 함량은 감소하는 경향이였으며, 건조온도가 높을수록 감소하는 폭이 컸다. 그리고 저장온도가 높을수록 저장기간이 길수록 아미노산의 함량이 감소하는 폭이 더 크게 나타났다.

• 한국식품저장유통학회지
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• 제10권4호
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• pp.476-481
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• 2003

아가리쿠스 버섯에 있어 각 온도별 건조 품질을 살펴보았다. 우선 갓과 대의 건조시간은 5$0^{\circ}C$에서 모두 29시간이었으며 10$0^{\circ}C$의 경우 갓과 대 모두 10시간 소요되었으며 실온에서 음건할 때에는 갓과 대가 모두 3일 정도 소요되었다. 수분감소율은 온도가 높을수록 켰으며, 부위별로는 5$0^{\circ}C$에서 초기감소율이 갓보다 대가 크게 나타났으며 최종수분함량은 갓이 대보다 적었다. 반면에 10$0^{\circ}C$와 실온에서 갓의 수분감소율이 켰으며, 최종수분함량은 갓이 적었다. 수분활성도는 갓과 대가 모두 실온에서 음건, 5$0^{\circ}C$, 10$0^{\circ}C$의 순으로 낮았다. 수화복원력은 갓과 대 모두가 건조온도와는 관계없었으며, 실온에서 침지 120분까지 급격히 증가하여 이때에 최대치를 나타내었다. 색도는 갓에서의 전체적으로 건조 온도가 상승함에 따라 백색도를 나타내는 L 값이 낮아지는 것으로 조사되었다. 세부적으로는 L 값이 5$0^{\circ}C$에서의 시료가 가장 높았고 생것이 가장 낮았다. a 값은 생시료가 가장 높았고, 10$0^{\circ}C$ 건조시료가 가장 낮았다. b 값은 10$0^{\circ}C$에서 건조시료가 가장 높았고 생것이 가장 낮았다. 갈변도는 건조온도가 높을수록 높았으며 갓이 대보다 켰다. 이는 온도 상승이 건조 아가리쿠스의 품질을 저하한다는 것을 보여주었다. 관능검사결과 건조온도가 상승함에 따라 색과 외관품질이 떨어지는 것으로 조사되었다. 하지만 향에 있어서 건조 온도가 5$0^{\circ}C$이상에서 전체적으로 좋은 향이 나오는 것으로 확인되었다 결과적으로 5$0^{\circ}C$의 건조온도에서 아가리쿠스를 열풍 건조하는 것이 경제적 뿐만 아니라 품질면에서 가장 좋은 조건이라 조사되었다. 뿐만 아니라 아가리쿠스의 약리성분들은 열에 강한 특성이 있으므로 5$0^{\circ}C$에서 건조하여도 충분히 기능성 및 약리성에 영향이 없을 것으로 사료되었다. 하지만 앞으로 아가리쿠스의 약리성분을 중심으로 조에 온도에 따른 영향을 조사하여 적정온도를 결정할 수 있는 연구가 필요하리라 생각된다.

• 한국약용작물학회지
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• 제19권6호
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• pp.501-507
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• 2011

This experiment was carried out in order to collect the basic data on the standardization of the manufacturing process of Rehmannia glutinosa Libosch. var. purpurea Makino drying. By the drying methods of R. glutinosa, the content of water, inorganic components, reducing sugar, catalpol and benzo[${\alpha}$]pyrene were investigated. The water content was 15.6~17.2% when R. glutinosa was dried by cold-warm air moisture absorption drying method (CAMAD) at $60^{\circ}C$ during 6 days. Among of the inorganic components of R. glutinosa the K content was the most followed by P, Na, Ca and Mg. The reducing sugar content of R. glutinosa by the hot air drying method (HAD) was much more than that by the CAMAD. The catalpol content of R. glutinosa was not different by the drying temperature when it was dried by the CAMAD. The catalpol content of the large size tuber (about 50.0 g/unit) showed a tendency to increase from $60^{\circ}C$ until $70^{\circ}C$ drying temperature, but that of the small size tuber(about 4.0 g/unit) was decreased as being a trend as the drying temperature high when R. glutinosa was dried by the HAD, But the catalpol content R. glutinosa had a tendency to drop significantly at drying temperature above $80^{\circ}C$. The benzo[${\alpha}$]pyrene content was little detected when R. glutinosa was dried by both the SLD and the CAMAD, and the sampling by the HAD indicated within the scope of 5 ${\mu}g/kg$ which was the scope to regulate by Korean food and drug administration. In conclusion, it seemed that an appropriate drying temperature of R. glutinosa by the CAMAD and the HAD was about $60^{\circ}C$ and about $70^{\circ}C$, respectively, when we consider the catalpol content and benzo[${\alpha}$]pyrene detection in the manufacturing process of drying R. glutinosa.