• Korean Journal of Food Science and Technology
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• v.38 no.6
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• pp.751-755
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• 2006

Physicochemical properties of black rice flours (BRFs) produced under different milling conditions were investigated to explore their applications for various processed rice products. Moisture contents of BRFs after roll milling and subsequent hot-air drying or microwave drying were 10.3% and 14.4%, respectively. The BRFs with jet milling and subsequent hot-air drying or microwave drying showed moisture contents of 7.9% and 7.5%. Mean particle sizes of the BRFs obtained from roll milling, jet milling, and following air-classification were 150, 41.5, and 9.4 ${\mu}m$, respectively. Hunter L value and water soluble index (WSI) of BRFs increased with decreasing particle size, while Hunter a value decreased. Total polyphenol contents of 91.4-115.8 mg/100 g and total amino acids of 75.0-96.4 mg/100 g in three types of BRFs were higher as compared to those (6.3 mg/100 g and 30.5 mg/100 g) of polished rice flour (PRF). Physicochemical properties such as moisture content, color parameter, and WSI have close relationship with the particle size of BRFs prepared under different milling conditions.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.579-588
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• 2015

Recent climage changes have resulted in increases in rainfall intensity and flood frequency as well as the risk of flood damage due to typhoons during the summer season. Water-friendly facilities such as ecological parks and sports facilities have been established on floodplains of rivers since the river improvement project was implemented and increases in the flood levels of rivers due to typhoons can lead to direct flood damage to such facilities. To analyze the hydraulic influence of these water-friendly facilities on floodplains or to evaluate their stability, numerical analysis should be performed in advance. In addition, it is crucial to address the drying and wetting processes generated by water level fluctuations. This study uses a Nays2D model, which analyzes drying and wetting, to examine its applicability to simple terrain in which such fluctuations occur and to natural rivers in which drying occurs. The results of applying this model to sites of actual typhoon events are compared with values measured at water level observatories. Through this comparison, it is determined that values of coefficient of determination ($R^2$), mean absolute error (MAE), and root-mean-square error (RMSE) are 0.988, 0.208, and 0.239, respectively, thus showing a statistically high correlation. In addition, the results are used to calculate flood risk indices for evaluation of such risk for water-friendly facilities constructed on floodplains.

• Journal of the Korean Wood Science and Technology
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• v.22 no.1
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• pp.54-65
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• 1994

This research carried out to investigate the effects of inorganic materials in paper sludge on the thermal degradation and of paper sludge addition on physical and mechanical properties of paper sludge-wood particle mixed boards in comparison with unmodified particleboards. Also these unmodified particleboards and paper sludge-wood particle mixed boards were soaked in aqueous solutions of fire-retardant chemicals(diammonium phosphate and zinc chloride), and their fire retardancy were tested by oxygen index method and ISO ignition test to determine the feasibility of paper sludge, industrial waste, as a recyclable resource in fabrication of fire-resisting panels for building material. Since the redrying of fire-retardant treated particleboards and paper sludge-wood particle mixed boards were made by press drying method, this process was a simple and effective method. On the other hand, flexural bending strength and internal bonding strength were also analysed to evaluate mechanical properties through standard method.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.07a
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• pp.61-64
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• 2003

Optical resolution of a-amino acid (tryptophan and tyrosine) optical isomers was achieved by a pressure driven membrane separation process, using self-supporting crosslinked membranes base on polysaccharide with different swelling indices that ranged from 100 to 70%. The membranes prepared by casting and drying the polymer solution containing 5wt% acetic acid on an acryl plate followed by crosslinking with glutaraldehyde were characterized using such analytical methods as FTIR and swelling index measurements. On the way of separating the optical isomers, several experimental factors such as the concentration of the feed solutions, operating pressure and temperature, and degree of crosslinking of the membranes have been studied. When the chitosan membranes with 70% of swelling index were used , almost complete optical resolution was obtained; 97.92% of enantiomeric excess (ee %) and 2.26 g/$m^2$ㆍh of flux. The operating pressure and the concentration of feed solutions were respectively 1.0 kgf/$\textrm{cm}^2$ and 0.49 mmol/L.

• Journal of Powder Materials
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• v.28 no.3
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• pp.227-232
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• 2021

The purpose of this study is to optimize the powder formulation and manufacturing conditions for the solidification of an extract of the herb Bangpungtongseong-san (BPTS). To develop BPTS-loaded particles for the tablet dosage form, various BPTS-loaded particles composed of BPTS, dextrin, microcrystalline cellulose (MCC), silicon dioxide, ethanol, and water are prepared using spray-drying and high shear granulation (high-speed mixing). Their physical properties are evaluated using scanning electron microscopy and measurements of the angle of repose, Hausner ratio, Carr's index, hardness, and disintegration time. The optimal BPTS-loaded particles exhibit improved flowability and compressibility. In particular, the BPTS-loaded particles containing silicon dioxide show significantly improved flowability and compressibility (the angle of repose, Hausner ratio, and Carr's index are 35.27 ± 0.58°, 1.18 ± 0.06, and 15.67 ± 1.68%, respectively), hardness (18.97 ± 1.00 KP), and disintegration time (17.60 ± 1.50 min) compared to those without silicon dioxide. Therefore, this study suggests that particles prepared by high-speed mixing can be used to greatly improve the flowability and compressibility of BPTS using MCC and silicon dioxide.

• Clinical and Experimental Reproductive Medicine
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• v.21 no.2
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• pp.207-214
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• 1994

This study was carried out to develop the methodology of chromosome preparation from blood cultures in mammals which included human, mouse, cattle and pig. For karyotyping, 0.5-5.0ml of peripheral blood were collected and cultured. The satisfactory results were obtained from macroculture and microculture in all species. In culture, the patterns of cell growth were no difference among media except serum concentration and mitogen supplement. The presence of mitogen and fetal bovine serum in medium significantly affected the mitotic index. The optimal culture condition was 37$^{\circ}C$ for 3 days. And the concentration of colcemid and reincubation time also affected the chromosome morphology. In harvest, chromosome patterns were mainly affected on hypotonic treatment which included treated time and temperature, dropwise of fixative solution, and drying after slide preparation.

• Journal of the Korean Society of Tobacco Science
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• v.5 no.2
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• pp.9-15
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• 1983

The effect of leaf dehydration process and air flow capacity of bulk curing on physical properties and composition of cured leaves was studied, respectively, during flue- curing. Cured leaves from excessive moisture during yellowing stage and those from rapid dehydration Process inevitably during later stages, tend towards lower equilibrium moisture contents, higher shatter index, hither protein nitrogen, and leaf scalding or deterioration of Beaves with redish cast. Early dehydration at the yellowing stage re suited in increasing of p Bamitic, stearic, linoleic, and linolenic acid contents, but showed reduction of brightness difference between upper and lower surface of the cured leaves, Leaf surface lipid decreased with the progress of curing stages, more conspicuously during later stage. Lowering air flow capacity of fan by 50oye during stem drying stage resulted in increasing of leaf surface lipid and 25oye decreasing of electric power consumption , but curing period and kerosene consumption were not affected.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.405.1-405.1
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• 2002

The amount of water for the cultivation of citrus is different based on the growing period. The water content in the leaves of citrus can be a index for watering during cultivation. The purpose of this study is to determine non-destructively the water content of Citrus leaves by using near infrared spectroscopy (NIRS). Citrus leaves were prepared from satsuma mandarin leaves (Citrus unshiu Marc. var. okitsu) ranging from 62.20 to 69.98% of water content by loss on drying, NIR reflectance spectra of Citrus leaves were acquired by using a fiber optic probe. (omitted)

• Journal of Environmental Health Sciences
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• v.36 no.2
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• pp.95-107
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• 2010

Hand-washing is one of the major factors in personal hygiene and public health. This study was undertaken to investigate the hygienic behavior of food-service employees, focusing on awareness of hand washing, hand washing practices, and the load of index microorganisms (aerobic plate count, total and fecal coliforms, Escherichia coli, and Staphylococcus aureus) on the hands of food-service employees. A questionnaire survey completed by direct interview, direct observation of restrooms by the researcher and trained observers, and microbiological examination according to the Food Code of Korea were carried out. In the survey, a positive attitude toward hand washing compliance was reported; however, improper hand washing and poor hand hygiene of the food-service employees were seen under direct observation. Significant differences (p<0.05) were found between the questionnaire survey and the direct observations in hand washing compliance after using the toilet, duration of hand washing, use of hand washing agents, use of hand washing tools, washing of different parts of the hands, hand-drying method, temperature of water, and method of turning off the water. Samples taken from employees' hands before washing showed higher levels of bacteria than those taken during work and/or after washing (p<0.05). Poor hand washing practices were indicated by the positive results for total and fecal coliforms, E. coli, and S. aureus on the hands of some food-service employees. This study showed that there is a marked difference between the food-service employees' awareness of hand-washing and their actual hand-washing practices. The poor hand hygiene of and improper hand washing by the food-service employees should be addressed for improved food safety.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.9-18
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• 2021

In this study, the overconsolidation ratio (OCR) of soft clay soil was calculated by conducting an indoor physical experiment and a dynamics test using undisturbed soil samples from a soft clay soil field in South Korea. The OCR by depth was predicted by comparing the experimental results with the existing empirical equations. Methods using the liquidity index and the existing empirical equation by the Naval Facilities Engineering Systems Command (NAVFAC) were examined, and the results were compared with the actual measured values. The method using the liquidity index was found to be suitable for estimating the rough OCR of the ground. However, the effect of drying was not considered for the ground above the groundwater level. Therefore, an equation for the correlation equation between the depth and OCR of each region, including the ground above the groundwater level, was proposed. The proposed equation was applied to the OCR prediction of the adjacent area. The predicted values in the area composed of clay (CL, CH) were found to be in good agreement with the actual values. In the region composed of silt (ML), however, the predicted values were not consistent with the actual values. This suggests that the sedimentation and compositional characteristics, rather than the engineering characteristics of the soil, are important factors that affect the OCR prediction.