• Journal of Korean Society for Quality Management
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• v.44 no.3
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• pp.487-508
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• 2016

Purpose: Current testing method for drying rate used in military textiles has different results according to the public testing institute. So the purpose of this study was to suggest the alternative method which secure the reliability of the drying rate test. Methods: We measured the drying rate by various test methods for military clothes 14 species including quick drying function and compared the test results. Also, the collected data through the test was analyzed using one-way ANOVA. The p-value of results was compared by various testing institutions. Results: The results of this study are as follow; A deviation occurred among the testing institutions in original test method(KS K 0815). Whereas it is verified that there is no deviation among the institutions in 5% significance level by another test method(ISO 17617). Also it would increase work efficiency by reducing the testing time required to test by using ISO 17617. Conclusion: Based on the results, we can suggest the reliable test method of the drying rate.

• Journal of Biosystems Engineering
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• v.43 no.3
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• pp.211-218
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• 2018

Purpose: The present study investigated the nutritional and organoleptic characteristics of two African leafy vegetables (ALVs)-jute mallow (Corchorus olitorius L) and cowpea (Vigna unguiculata)-at various drying temperatures. Methods: The thin-layer drying of cowpea leaves and jute mallow was studied at various temperatures ($40-100^{\circ}C$) in a convective laboratory dryer, and the nutrient profiles of the dried vegetables were determined. The nutrients considered were vitamins B2 and C, and ${\beta}$-carotene. The level of vitamin C was determined by high-performance liquid chromatography (HPLC), whereas the levels of ${\beta}$-carotene and vitamin B2 were determined by titration. Results: ${\beta}$-carotene was the most stable nutrient, whereas vitamin C was the least stable nutrient in both cowpea leaves and jute mallow. The drying parameters-temperature and time-revealed that temperature had the most profound effect on vegetable nutrient stability. Organoleptic tests were carried out on the fresh and dried vegetable; there were no significant differences in preference between the fresh and dried ALVs (95% confidence interval). Conclusions: The present study revealed that the vegetables can be preserved by drying, and the study could be used as a guide for effective drying of those vegetables.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.6
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• pp.505-511
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• 2014

In this paper, silver pastes were printed on polyethylene terephthalate (PET) film using screen printing and evaluated the drying characteristics by using dry oven and NIR drying system. The printed Ag films were dried at $140^{\circ}C$ and the drying time was changed from 10 to 90 seconds. To evaluate the electrical properties of printed Ag film, sheet resistance was compared. The sheet resistance of the dried thin silver film by using NIR drying system more rapidly decreased. To clarify this phenomena, the morphology and component of the dried surfaces were measured by using the scanning electron microscope (SEM) and the energy dispersive X-ray Spectroscopy (EDX), respectively. In the EDX measurement results, the oxidation of the surface was observed in the dried thin film by using the dry oven. The NIR drying system is more applicable than conventional hot air drying to apply continuous printing system.

• Textile Coloration and Finishing
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• v.7 no.4
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• pp.33-38
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• 1995

In resist-discharge printing of cotton fabrics with reactive/reactive dyes the effects of intermediate drying on the white and the colored resist-dischargeabilities were studied. From the results of resist-discharge printing in case of 75% pick up, it was found that the most effective condition of intermediate drying which could at once prevent bleeding and improve the resist-dischargeability was 11$0^{\circ}C$ x 1min. The drying condition of 10$0^{\circ}C$ x 2min or 12$0^{\circ}C$ x 1min can be also recommended. It is important to pay close attention to the intermediate drying temperature and time. Because in case of 75% pick up when drying was carried on at 11$0^{\circ}C$ or 12$0^{\circ}C$ for more than 1 minute the resist-dischargeability was greatly lowerd by the fast fixation of ground color caused by high temperature, and in case of 100 % pick up the insufficient drying of ground color caused the resist-dischargeability to lower with giving rise to various troubles such as bleeding and smearing.

• Journal of the Korean Wood Science and Technology
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• v.41 no.5
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• pp.456-465
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• 2013

Log cross sections of yellow poplar were dried in a radio frequency vacuum (RFV) dryer under alternating vacuum and release (AVR) process. The average moisture content (MC), temperature and vapor pressure at the volumetric center were monitored as functions of time. Three different log thicknesses (33, 60 and 75mm) were tested. The results show that the AVR process caused an increase in the drying rate when the moisture content was above fiber saturation point (FSP, about 30% MC) but that it had an inverse effect on the drying rate when the MC was below FSP. The effect of the AVR process on the drying rate decreased, and the severity of heart checks increased, with the increase in the thickness of the specimens.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.15 no.4
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• pp.362-371
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• 1986

In the normal Refrigeration process, the condensation heat of refrigerant s not been used because of its low-temperature waste heat. To recover the condensation waste heat of R-12 refrigerator, a drying and hot water system was designed and experimented. The results obtained were summarized as follows: 1. As the temperature a temosphere was increased, the temperature of discharge gas of compressor was increased. And the temperature was $80-84^{\circ}C$ for air condensing type and was $68-71^{\circ}C$ for water condensing type during summer. 2. The condensation waste heat could be obtained up to $50-55^{\circ}C$ of drying heat-source and Hot water in summer. In this case, recovered rate was about $73\%$. And the more temperature of drying Heat-source and Hot water were increased, the more a recovered rate were decreased. 3. When comparing drying characteristics of Agro-products in dryer of waste heat utilization and Hot air, there was no quality difference in products. But drying time of the former was 3 Hours longer than the latter. 4. The condensation waste heat of compressor could be applied into the drying of marine products, the predrying of agro-products and making hot water. And showed high possibility of the waste heat using in low-temperature storage.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.133-138
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• 2001

In this paper, we have investigated the drying characteristics of waste sludge in a rotary dryer equipped with disintegration device. The sludge samples($moisture\;contents\;:\;70{\sim}85%\;W.B.$) used in the experiment were mainly a soybean and an alcohol fermentation sludges in food industry, or sewage sludge. It was studied by measuring the change of moisture contents that the shaft speed($operating\;range\;:\;100{\sim}250rpm$) affected on the drying rate and the particle size distribution of the dried solid. The dried granular products of the diameter of 1 to 5mm are obtained from sludge materials. In the results, as the increased of shaft speed, the particle size and the moisture contents of dried solid was decreased, and the retention time was increased.

• Structural Engineering and Mechanics
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• v.52 no.1
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• pp.97-113
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• 2014

In the present work appropriate concrete material models have been proposed to predict drying shrinkage and specific creep of High-performance concrete (HPC) using Artificial Neural Network (ANN). The ANN models are trained, tested and validated using 106 different experimental measured set of data collected from different literatures. The developed models consist of 12 input parameters which include quantities of ingredients namely ordinary Portland cement, fly ash, silica fume, ground granulated blast-furnace slag, water, and other aggregate to cement ratio, volume to surface area ratio, compressive strength at age of loading, relative humidity, age of drying commencement and age of concrete. The Feed-forward backpropagation networks with Levenberg-Marquardt training function are chosen for proposed ANN models and same implemented on MATLAB platform. The results shows that the proposed ANN models are more rational as well as computationally more efficient to predict time-dependent properties of drying shrinkage and specific creep of HPC with high level accuracy.

• Korean Journal of Food Science and Technology
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• v.53 no.1
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• pp.85-91
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• 2021

The physicochemical properties of deodeok (Codonopsis lanceolate) was investigated in relation to the different steaming time and cycles of steaming and drying (S/D). Additionally, the quality characteristics of Makgeolli with different amount (0-0.45%) of steaming and drying deodeok (SD) were measured comparison to non-steaming and drying deodeok (NSD). L⁎ values of deodeok tended to decrease as the number of S/D cycles and steaming times increased, while BI showed the opposite trend for L⁎ values. Reducing sugar increased significantly from 1 to 3 S/D cycles and decreased thereafter (p<0.05). Also, processed with steaming for 4 h and 5 S/D cycles had the highest antioxidant properties. Principal component analysis (PCA) revealed that the S/D process notably influenced the properties of deodeok. Quality characteristics of Makgeolli showed that 0.45% SD resulted in higher antioxidant properties than control or NSD.

• Steel and Composite Structures
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• v.47 no.4
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• pp.539-550
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• 2023

Owing to the obstruction of section steel on the moisture diffusion in concrete, the existing shrinkage prediction models overestimate the time-dependent deformation of steel reinforced concrete (SRC) columns, particularly for the SRC columns with enclosed section steels. To solve this issue, this study deals with analytical and experimental studies on the drying shrinkage for this type of column. First, an effective method for predicting the drying shrinkage of concrete based on finite element model is introduced and two crucial parameters for simulation of humidity field are determined. Then, the drying shrinkage of SRC columns with enclosed section steels is investigated and two modified parameters, which depend on the ambient relative humidity and the ratio of section steel size to column size, are introduced to the B3 model. Finally, an experiment on the shrinkage deformation of SRC columns with enclosed section steels is conducted. Comparing the predicted results with the experimental ones, it demonstrates that the modified B3 model is quite reasonable.