• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.1
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• pp.60-65
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• 2000

Biosorptions of Cr and Pb were evaluated for 23 species of marine algae collected from a Korean coast. Among a variety of species for biosorbent potential, Sargassum species showed higher uptake capacity for Cr and Pb. An adsorption equilibrium was reached in about 1 hr for Cr and 30 min for Pb. The maximum uptake capacity was136.0 mg Cr/g biomass and 232.5 mg Pb/g biomass, respectively. In Pb biosorption in the column packed with Sargassum tbunbertii, 300 and 200 bed Tolumes at the concentration of 50 mg/L in feed solution were processed at the column residence time of 5 and 10 min before the column breakthrough point occurred. The elutions with 0.1 M HCl solution were more than $95{\%}$. The high efficiency of continous biesorntion and elution (3 cycles) indicated that Sargassum thunbergii was an effective biosorbent for Pb recovery.

• Journal of Nutrition and Health
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• v.16 no.3
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• pp.146-153
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• 1983

In this study, buckwheat four was classified by the order of extraction from the inmost layer to the outmost layer, and was designated as $B_1,\;B_2,\;B_3,$ and the mixed flour of $B_1,\;B_2,\;B_3$ (1:1:1) was named $B_0$. To improve the dried noodle-making properties, various levels of strong wheat flour and additives such as sodium alginate (SA) and xanthan gum(XG) were added to buckwheat. 1) The buckwheat $B_2$ and $B_3$ flours contained much higher amounts of crude ash, protein and fat than the $B_1$ flour. 2) Buckwheat $B_3$ flour demonstrated lower maxium viscosity value by amylograph than the $B_1$ flour, but it demonstrated 2 times higher maximum viscosity value than wheat flour. Buckwheat $B_1$ flour demonstrated 4-5 times higher maximum viscosity value than wheat flour. Addition of SA and XG increased the viscosity of the flour mixtures. 3) It was possible to make dried noodles from the composite flour of (buckwheat 40 %+wheat 60 %). The lesser the quantity of buckwheat flour was, the better the kneading property of mixed flour was. 4) SA and XG, which were added at the level of 1.0-1.5%, significantly improved dough making properties and the cooking quality of the noodles.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.1
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• pp.99-105
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• 2012

Purpose: The purpose of this study is to demonstrate inactivation effect of UVA-LED ultraviolet radiation upon Pseudomonas aeruginosa and Staphylococcus aureus which are the major bacteria causing eye diseases. Methods: The small sterilization device was made using UVA-LED of 400 nm. After Pseudomonas aeruginosa was diluted to $10^{-7}$ and Staphylococcus aureus to $10^{-5}$ and diluted solutions were put onto each liquid medium. They were irradiated by 400 nm of UVA for different amount of time; 15 min, 30 min, 60 min, 120 min, 240 min, 360 min and 480 min each. Results: The data from sterilization test was solved to regression line equation and the target log inactivation was obtained. The 3 log inactivation UV irradiation value of Pseudomonas aeruginosa was 54,847 UV dose ($mJ/cm^2$) and irradiation time was 135.42 min while the 3 log inactivation of Staphylococcus aureus was 39,066 UV dose ($mJ/cm^2$) and irradiation time was 98.72 min. Conclusions: The inactivation effect of sterilization method using 400 nm of UVA-LED upon Pseudomonas aeruginosa and Staphylococcus aureus has been verified and it is considered as a useful method in inactivating the contact lenses.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.649-655
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• 2010

This study investigated the degradation of phenol using sonication and/or UV-C. The effects of frequency, temperature, pH in solution, argon purging, with UV intensity were estimated in sonication-only, UV-only, and the combined reaction of sonication with UV. The optimum condition for degrading phenol in the sonication-only reaction was 35 kHz, $5^{\circ}C$, and pH 4. As this condition approximately 30% degradation of phenol was achieved within 360 min. However, phenol in the UV-only at $19.3\;mw/cm^2$ under the same condition was completely degraded within 60 min. In the combined system of sonication with UV, the degradation of phenol was well fitted to first-order rate model, and phenol was completely degraded within 360 min and 45 min at UV intensity of $7.6\;mW/cm^2$($17.3{\times}10^{-3}\;min^{-1}$) and $19.3\;mW/cm^2$($138.1{\times}10^{-3}\;min^{-1}$), respectively. Adding methanol, as a radical scavenger, in the phenol degradation in the sonication reaction indicates that OH radical is a major factor in the degradation of phenol. The order of degradation efficiencies of phenol was in the order of as follows; combined reaction of sonication with UV > UV-only > sonication-only.

• Journal of Life Science
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• v.29 no.12
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• pp.1358-1363
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• 2019

In this study, the effect on the free amino acid content and anti-oxidative activity of Arctium lappa samples by heat treatment were compared to obtain data on the conditions required for properly processing the root as a raw material for tea. The results of DPPH and ABTS radical scavenging activity assays showed that 180℃-4 min and 200℃-3 min treatments retained relatively high activity. All heat treatment conditions showed increased polyphenol content compared to the initial sample value of 42.72 mg/l, and the 180℃-4 min and 200-3 min treatments were higher than the others at 60.09 mg/l and 62.74 mg/l, respectively. In the free amino acid analysis of the A. lappa root tea, the tendency of the initial content was confirmed to decrease as temperature and time increased. Changes in phenylalanine, histidine, leucine, and isoleucine were found to be high, while aspartic acid and proline changes were relatively low. Overall, amino acid content decreased significantly under heating conditions above 180℃-3 min and 200℃-2 min. From these results, heat treatment of A. lappa root at 180℃-4 min was deemed optimal based on anti-oxidative activity and free amino acid content.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.15-22
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• 1970

This experiment is to investigate the influence on business by varying the scouring condition of raw silk. The conditions of experiment are changed by temperature, time concentration and scouring reagent as well as the pH value of scouring solution, involving the repeat number of treatment in the same reagent solution. The results are as follows. 1) The shorter the scouring time, the more lousiness showed on law silk. The difference of lousiness quantity are especially remarkable between 30 min. and 60min, while the appearance of lousiness is slight between 50min. and 90min. 2) The lousiness shape was just like splited end and short wool fiber type during than 60 min. scouring, and splited end and long wool fiber type was appeared during 120 min. scouring. 3) The seperation of threads on silk panel was difficult with undissolved sericin in case of lower than 90$^{\circ}C$ of scouring temperature, so that it was almost impossible to inspect lousiness. 4) In case of repeating one after another scouring in the same solution, the more number of treatment, the less sho wed lousiness. Little difference were appeared in the quantity of lousiness from first to eighth repeated scouring, while large difference of quantity was appeared between 8th and 9th repeated scouring. 5) The quantity of lousiness was also increased until scouring reagent (Marseilles soap) is added to 0.75％, but rather decreased with more than 0.75％ of soap. The most variety of lousiness quantity was occured when the concentration of soap is changed from 0.15％ to 0.20％. 6) The peculiarities of lousiness shape by the concentration of scouring reagent were as followings; most of lousiness are splited end short wool fiber type with lower wool fiber type with higher than 0.75％, and the mixture of both the former and the latter with 0.5％ concentration. 7) The quantity of lousiness by the kind of scouring reagent was the least with 5％ of Na$_2$CO$_3$ solution, and the most with the mixture of 0.25％ Marseilles soap and 0.25％ Na$_2$CO$_3$. 8) The more increased pH value, the more lousiness showed. The peculiarities of lousiness shape was the splited end and short wool fiber type, and the end and long wool fiber type with higher value of pH 11 because of the decreased strength of threads and the cutting of brin. 9) With the discussions mentioned the above, the scouring conditions to decrease the lousiness quantity are summarized as follows. (1) It is better to take the possible long time of scouring. (2) Temperature should be kept higher than 95$^{\circ}C$ for complete scouring. (3) It was the best to use 0.5％ of Marseiles soap as scouring reagent. (4) No good results were produced by using the mixture of scouring reagent. (5) The best pH range of scouring solution was 9.5 to 10.5.

• Journal of dental hygiene science
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• v.10 no.6
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• pp.451-457
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• 2010

It is well known that most of the beverages on sale contain acid. Among these beverages, one of the most typically purchased products is Coca-Cola ($Coke^{(R)}$), which affects the demineralization of the tooth enamel surface. However other beverages also affect the erosion of the tooth enamel surface. Therefore, the aim of this study was to observe the influence that acid containing beverages have upon the tooth enamel surface. In this study, 30 enamel specimens were obtained from extracted maxillary third molars without cracks. The study measured the pH concentrations and the Ca and P concentration levels of the acidic beverages. The control without exposure was kept in distilled water, and each enamel specimen was stored for 30-min, 60-min, and 120-min. The erosion effect of the enamel surface was observed by SEM. The results obtained from this study can be summarized as follows: 1. The pH concentration of acidic beverages, without milk, was 3.105 on average. The beverages eroded the enamel surface and the erosion degree was determined by the pH concentration of beverages. 2. The erosion degree significantly increased by as the exposure time increased. The difference in the erosion degree between the 30-min group and the 60-min and the 120-min group was significant, but the erosion degree of the 120-min group was significantly less than that of the initial group. 3. When compared with the beverages containing similar pH concentrations, the demineralization degree of the beverages containing higher concentrations of Ca and P was lower.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.367-372
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• 2002

In order to utilize safflower seed effectively as a food material, it was processed at the conditions including roasting temperature/time of 170$\^{C}$/10 min to 210$\^{C}$/30 min, ethanol concentration of 0 to 100% (V/V) and enzyme hydrolysis with $\alpha$-amylase, $\beta$-amylase, amyloglucosidase and cellulase. Safflower seed extracts had the highest soluble solid content at the condition of 60% ethanol concentration, roasting at 190$\^{C}$ for 20 min and hydrolysis with amyloglucosidase. Total phenolic compounds increased with the ethanol concentration, showing the highest at the condition of 80% ethanol, roasting at 170$\^{C}$ for 30 min and hydrolysis with amyloglucosidase. High level total flavonoid was observed at the condition of 80% ethanol, roasting at 210$\^{C}$ for 30 min and hydrolysis with amyloglucosidase. Safflower seed had sucrose as major free sugar as well as xylose and arabinose as minor free sugars. Organic acids in safflower seed included oxalic, citric, magic and fumaric acid. Serotonin I (N-[2-(5-hydroxy-1H-indo-1-3-yl)ethyl]ftrulamide) and serotonin II (N-[2-(5-hydroxy-1H-indol-3yl)ethyl]-p-coumaramide) as antioxidant compounds increased with ethanol concentration, showing the highest revel at 60% ethanol. Acacetin content increased with temperature and roasting time, with a maximum of 69.47 mg% at 210$\^{C}$ for 30 min.

• Journal of Korea Water Resources Association
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• v.53 no.12
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• pp.1159-1172
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• 2020

This study applied deep convolution neural network based on U-Net and SegNet using long period weather radar data to very short-term rainfall prediction. And the results were compared and evaluated with the translation model. For training and validation of deep neural network, Mt. Gwanak and Mt. Gwangdeoksan radar data were collected from 2010 to 2016 and converted to a gray-scale image file in an HDF5 format with a 1km spatial resolution. The deep neural network model was trained to predict precipitation after 10 minutes by using the four consecutive radar image data, and the recursive method of repeating forecasts was applied to carry out lead time 60 minutes with the pretrained deep neural network model. To evaluate the performance of deep neural network prediction model, 24 rain cases in 2017 were forecast for rainfall up to 60 minutes in advance. As a result of evaluating the predicted performance by calculating the mean absolute error (MAE) and critical success index (CSI) at the threshold of 0.1, 1, and 5 mm/hr, the deep neural network model showed better performance in the case of rainfall threshold of 0.1, 1 mm/hr in terms of MAE, and showed better performance than the translation model for lead time 50 minutes in terms of CSI. In particular, although the deep neural network prediction model performed generally better than the translation model for weak rainfall of 5 mm/hr or less, the deep neural network prediction model had limitations in predicting distinct precipitation characteristics of high intensity as a result of the evaluation of threshold of 5 mm/hr. The longer lead time, the spatial smoothness increase with lead time thereby reducing the accuracy of rainfall prediction The translation model turned out to be superior in predicting the exceedance of higher intensity thresholds (> 5 mm/hr) because it preserves distinct precipitation characteristics, but the rainfall position tends to shift incorrectly. This study are expected to be helpful for the improvement of radar rainfall prediction model using deep neural networks in the future. In addition, the massive weather radar data established in this study will be provided through open repositories for future use in subsequent studies.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.22-29
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• 2005

This research was carried out not only to examine the proper manufacturing condition for white charcoal board in relation to charcoal particle size and final mat moisture content (FMC), but also to maintain the advantageous properties of white charcoal as a well being building material against the sick house problem. Excellent functional white charcoal board was produced with two groups of FMC 20~25% and FMC 36~60%. The latter showed best results among tested samples in two types which are #40-60type-P15%, M5%, FMC 60% and mixed type-P15%, M5%, FMC36% with non formaldehyde adhesives [MDI (M), poly vinyl acetate emulsion (P)] and three stage pressing cycle of 30-10-$30kgf/cm^2$ (1 min.-1.5 min.-6 min.). The former gave highly acceptable results in two types which are #6 over-M15%FMC25% and mixed type-M25%FMC20%. White charcoal board gave excellent in dimensional stability, gas adsorption and far-infrared emission.