• Solar Energy
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• v.11 no.3
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• pp.21-30
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• 1991

In-bin grain drying experiments were performed to investigate the drying characteristics between natural air and solar heated-air drying system of rough rice. A computer simulation model for solar drying system of rough rice resulted in a good agreement between the experimental and predicted moisture content. In order to save the electric energy consumption of fan, airflow rates control system using inverter was developed and resulted in the effect of energy saving.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.512-515
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• 1995

In order to examine the effect of rehydration methods on viability after freeze-drying of Streptomyces aureofaciens, we labeled the DNA of S. aureofaciens with $^3H-adenine$. Extracellular radioactivity levels appeared to be high in the rehydrated solutions after freeze-drying than freezing-thawing. In effects of rehydration after freeze-drying, the viability of the cell appeared about 20% in case of with admitting air at single ampule, but that of which appeared about 91% in case of without admitting air at double ampule. Thus, S. aureofaciens cells were damaged during the process of rehydration after freeze-drying.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.122-125
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• 2000

CFRD (Concrete Faced Rockfill Dam) face slab concrete has a much capability to occur crack due to drying shrinkage, hydration heat and bas compaction etc. Because of crack of concrete induce structural problem and decrease durability of concrete, it is need to reduce crack of concrete. This is an experimental study to analyze the effect of fiber reinforced on CFRD face slab concrete. for this purpose, it was investigated and analyzed the engineering properties of plain concrete and polypropylene fiber reinforced concrete (PFRC) according to test result ; the test include slump, air content, compressive strength, tensile strength, drying shrinkage and permeability etc. As the results, it was found permeability and drying shrinkage of PFRC less than that of plain concrete.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.423-426
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• 2006

Paper has fibers and fines network structure and it is strongly affected by interface bonding between fibers. Depending on the inter-fiber bonding, paper bulk is determined. Fines play an important roll in Campbell and consolidation effect through wet pressing and drying operations. Refined Sw-BKP, Hw-BKP and BCTMP fines were used to investigate the fines effect. Wet-web strength, breaking length, scattering coefficient, and hydrodynamic specific volume were measured. According to the result of experiments, chemical and morphological compositions of fines do not strongly affect to wet-web forming, but strongly affect to drying operations which form hydrogen bonding among fiber-fines-fiber matrixes. Paper bulk should be controlled by the extent of hydrogen bonding between fibers during drying operations.

• Journal of the Korean Society of Tobacco Science
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• v.8 no.1
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• pp.41-48
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• 1986

This experiment was carries out to study on the effect of temperature raising rate to chemical composition of tobacco leaves during the midrib drying stage of flue-curing. The results were as follows : In the case of the temperature raising rate became more rapidly during midrib drying stage. It had a tendency to increase in oxailic acid, succinlc acid, ammonia, polyphenol; there was a large loss of total sugar, reducing sugar, malic acid, palmitic acid and linolenic acid; leaf color became more reddish; the leaf quality index value decreased, thereby the quality of external appearance deteriorated. It is desirable that the temperature raising rate had to be more slowly.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.1
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• pp.52-60
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• 2009

A printing defect known as fluting (or waviness) of the web printed by heatset web offset printing process is one of the chronically serious problems deteriorating print quality. In this paper, fluting occurrence on uncoated papers was explored in terms of many printing conditions including drying temperature, fountain solution amount, ink supply, and press configurations. For this purpose, fluting on prints from real press runs was appraised in a quantitative manner. As results, ink supply was a distinctive factor for fluting such that the lower ink amount, the milder fluting. However increase in fountain solution seemed to make fluting severer while the effect of drying temperature was inconsistent for each paper. This result might indicate variable drying requirements for each paper. Thereby it was suggested that the optimum drying conditions related to the printabilities of each paper need to be established to minimize fluting potential. A press with short dryer and drastic cooling unit produced higher fluting. Suggestions for future work were given along with interpretation for the results.

• Journal of the Korean Ceramic Society
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• v.42 no.5 s.276
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• pp.333-337
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• 2005

In order to improve the performance of green emitting phosphors for plasma display panel, the $Zn_2SiO_4:Mn,Al$ phosphors were synthesized using sol-gel technique and studied using SEM and VUV photoluminescence spectrometer. pH values of the starting solutions (pH = 0.5$\~$2.34) were controled by HCl as the catalysis of hydrolysis and wet gels were dried at $80^{\circ}C$ and $120^{\circ}C$, respectively. We investigated the effects of pH and drying temperatures during sol-gel processes. The results indicated that the phosphor prepared at pH = 1 showed the maximum emission intensity in both drying conditions and the effect of pH of the starting solution on morphology were increased with particle size as HCl and phosphor dried at high temperature showed more spherical and smaller particles than at low.

• Magazine of the Korea Concrete Institute
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• v.6 no.4
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• pp.123-130
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• 1994

The advantages of polypropylene fibers in concrete have been widely advertised abroad. However, the behavior of concrete containing plastic fibers has not been fully understood. In order to study the effect of fibers on possible crack control, the effects of fikrs on workability and drying shrinkage have been studied. 'The workability change due to the addition of fibers has been studied. and full size concrete slabs have been cast at field to investigate the effect of fibers on the shrinkage properties. Moisture absorption characteristics of fibers has also been studied. The addition of fibers was found to reduce workability significantly and required additional water to maintain the workability, which caused increased drying shrinkage depending on the amount of addition, but strength has not been changed significantly.

• Geomechanics and Engineering
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• v.28 no.2
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• pp.107-116
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• 2022

The steady state of unsaturated soil takes a long time to achieve. The soil seepage behaviours and hydraulic properties depend highly on the wetting/drying rate. It is observed that the soil-water characteristic curve (SWCC) is dependent on the wetting/drying rate, which is known as the dynamic effect. The dynamic effect apparently influences the scanning curves and will substantially affect the seepage behavior. However, the previous models commonly ignore the dynamic effect and cannot quantitatively describe the hysteresis scanning loops under dynamic conditions. In this study, a dynamic hysteresis model for SWCC is proposed considering the dynamic change of contact angle and the moving of the contact line. The drying contact angle under dynamic condition is smaller than that under static condition, while the wetting contact angle under dynamic condition is larger than that under static condition. The dynamic contact angle is expressed as a function of the saturation rate according to the Laplace equation. The model is given by a differential equation, in which the slope of the scanning curve is related to the slope of the boundary curve by means of contact angle. Empirical models can simulate the boundary curves. Given the two boundary curves, the scanning curve can be well predicted. In this model, only two parameters are introduced to describe the dynamic effect. They can be easily obtained from the experiment, which facilitates the calibration of the model. The proposed model is verified by the experimental data recorded in the literature and is proved to be more convenient and effective.

• Korean Journal of Medicinal Crop Science
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• v.25 no.2
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• pp.89-94
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• 2017

Background: The purpose of improving the quality of oriental medicinal herbs is to contribute to the improvement of the income of farm. The present study investigated the effect of reasonable drying methods, different storage conditions and packageing materials on quality and stability of Scutellaria baicalensis Georgi and for developing GAP (good agricultural practice) guide book. Methods and Results: Three methods of drying Scutellaria baicalensis roots produced over two years were used to estimate loss rate owing to drying, storage, and packaging. The methods of drying were categorized into natural drying (36 - 60 h by sunshine), drying with heat dryer (2 - 10 h), or drying with gas bulk dryer (2 - 10 h). After cleaning, and initial drying for a few days under controlled temperature conditions, the second phase of drying was carried out at 35, 45 and $55^{\circ}C$. Changes in hunter color values and quality under the two studied storage treatments (at $20^{\circ}C$ indoors and at $4^{\circ}C$ in a refigerator) were evaluated. Storage period for 60, 120, and 180 days in three packaging materials, PE (polyethylene package), PP (polypropylene gunnysack), and WP (watertight packing paper) were studied. Conclusions: Initial cleaning, reasonable gas drying and hot air drying, and drying in an oven at 35 and $45^{\circ}C$ after cutting the roots resulted in the lowest loss rates in S. Baicalensis root. Hunter color valuse indicated that stroage of dry roots at room temperature was better than PP packaging, and that cold stroage was better than PE packaging for long-term stability.