• Journal of the Korean Wood Science and Technology
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• v.32 no.4
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• pp.46-51
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• 2004

The objective of this study was to evaluate the applicability of high temperature drying to pitch pine (Pinus rigida) lumber, especially intended for use as lamina of structural glued laminated timber (glulam), to enhance the efficient utilization and provide added-value to that species. The high temperature schedule and drying procedures utilized were shown to be reasonable for drying glulam lamina due to the occurrence of small moisture gradients, minimal residual drying stress, and low warpage. Through preliminary tests, it was confirmed that residual resin at lamina surfaces did not adversely affect the gluing process. However, quantitative analysis of resin is required for developing a method to constrain the occurrence of pitch trouble with respect to decreasing long-term adhesive and finish durability of glulam in use after manufacturing. The final moisture content of high temperature dried lamina was much lower than target moisture content and discoloration was more severe than anticipated. In a further study, it will be necessary to determine the optimal drying conditions, such as temperature, humidity, drying time, and top load restraint level, which could best control discoloration, warpage, and moisture content of the lamina, while minimizing fuel expense.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.12
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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.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.58-66
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• 2016

This study was performed to investigate drying characteristics and quality properties of dried persimmon with vacuum drying process. Drying characteristic curve of the dried persimmon showed that the constant rate drying period and falling rate drying period exist definitely. $_{\circ}Brix$, sugar content and hardness value of the dried persimmon increased as the vacuum pressure and heating temperature increased, but L value of the dried persimmon lower. The results indicated that the optimal conditions were at vacuum pressure of 40~50kPa abs., heating temperature of $30^{\circ}C$ and drying time of 3~4days.

• Journal of the Korean Wood Science and Technology
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• v.22 no.1
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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.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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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.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.145-148
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• 1989

Shiitake mushrooms were dried by hot air, far infrared and freeze dryers in order to compare qualities after drying. When hot air drying was performed with the four temperature variations ranged from $45\;to\;70^{\circ}C$, there was tendency to increase volume retention but decrease rehydration ratio, as drying temperature increased. And the largest amout of 5'-GMP was contained in mushroom dried at $50^{\circ}C$. For far infrared drying, volume retentions were lower but rehydration ratios were higher, as compared with hot air drying at the same temperature. In freeze drying, freezing rate had no influence on volume retention but rehydration ratio was highest value when frozen at $-18^{\circ}C$. As shelf temperature increased(drying rate increased), rehydration ratio increased. Also, contents of 5'-AMP, 5'-GMP and 5'-XMP increased with the increase of freezing rate and drying rate.

• Proceedings of the SAREK Conference
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• 2008.06a
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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.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.1
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• pp.29-33
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• 1989

As one of the application of microcomputer for data acquisition and temperature control of food drying process, these studies designed and built 'the interface system, measuring sensors of weight and temperature, temperature control system'. The basic and assembly language was used to operating these system. These system measured successfully the variables such as weight and temperature during food drying, and controlled Automatically the drying temperature.

• Journal of Biosystems Engineering
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• v.32 no.1 s.120
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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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• v.34 no.1
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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.