• Journal of Environmental Science International
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• v.16 no.4
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• pp.523-532
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• 2007

This study utilized the 1/25,000 topographic map of the upper area from the Geum-ho watermark located at the middle of Geum-ho river from the National Geographic Information Institute. For the analysis, first, the influence of the size of critical area to the hydro topographic factors was examined changing grid size to $10m{\times}10m,\;30m{\times}30m\;and\;50m{\times}50m$, and the critical area for the formation of a river to $0.01km^2{\sim}0.50km^2$. It is known from the examination result of watershed morphology according to the grid size that the smaller grid size, the better resolution and accuracy. And it is found, from the analysis result of the degree of the river according to the minimum critical area for each grid size, that the grid size does not affect on the degree of the river, and the number of rivers with 2nd and higher degree does not show remarkable difference while there is big difference in the number of 1st degree rivers. From the results above, it is thought that the critical area of $0.15km^2{\sim}0.20km^2$ is appropriate for formation of a river being irrelevant to the grid size in extraction of hydro topographic parameters that are used in the runoff analysis model using topographic maps. Therefore, the GIUH model applied analysis results by use of the river level difference law proposed in this study for the explanation on the outflow response-changing characters according to the decision of a critical value of a minimum level difference river, showed that, since an ogival occurrence time and an ogival flow volume are very significant in a flood occurrence in case of not undertow facilities, the researcher could obtain a good result for the forecast of river outflow when considering a convenient application of the model and an easy acquisition of data, so it's judged that this model is proper as an algorism for the decision of a critical value of a river basin.

• Journal of the Korean earth science society
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• v.34 no.7
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• pp.681-692
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• 2013

We aimed to evaluate the effectiveness of the Giggenbach bottle method and develop the related pretreatment and analytical methods using artificial fumarolic gases. The artificial fumarolic gases were generated by mixing $CO_2$, CO, $H_2S$, $SO_2$, $H_2$, and $CH_4$ gas streams with a $N_2$ stream sparged through an acidic medium containing HCl and HF, with their compositions varied by adjusting the gas flow rates. The resultant fumarolic gases were collected into an evacuated bottle partially filled with a NaOH absorption solution. While non-condensible gases such as CO, $H_2S$, and $CH_4$ accumulated in the headspace of the bottle, acidic components including $CO_2$, $SO_2$, HCl, and HF that were dissolved into the alkaline solution. Like other acidic components, $H_2S$ also dissolved into the solution, but it reacted with dissolved $Cd^{2+}$ to precipitate as CdS when $Cd(CH_3COO)_2$ was added. The non-condensible gases were analyzed on a gas chromatography. Then, CdS precipitates were separated from the alkaline solution by filtration, and they were pretreated with $H_2O_2$ to oxidize CdS-bound sulfide into sulfate. In addition, a portion of the solution was also pretreated with $H_2O_2$ to oxidize sulfite to sulfate. Following the pretreatment, the resultant samples were analyzed for $SO_4^{2-}$, $Cl^-$ and $F^-$ on an ion chromatography. In the meanwhile, dissolved $CO_2$ was analyzed on a total organic carbon-inorganic carbon analyzer without such pretreatment. According to our experimental results, the measured concentrations of the fumarolic gases were shown to be proportional to the gas flow rates, indicating that the Giggenbach bottle method is adequate for monitoring volcanic gas. The pretreatment and analytical methods employed in this study may also enhance the accuracy and reproducibility of the Giggenbach bottle method.

• Journal of the Korean earth science society
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• v.39 no.3
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• pp.228-240
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• 2018

Solar energy is calculated using meteorological (14 station), ceilometer (2 station) and microwave radiometer (MWR, 7 station)) data observed from the Weather Information Service Engine (WISE) on the Seoul metropolitan area. The cloud optical thickness and the cloud fraction are calculated using the back-scattering coefficient (BSC) of the ceilometer and liquid water path of the MWR. The solar energy on the surface is calculated using solar radiation model with cloud fraction from the ceilometer and the MWR. The estimated solar energy is underestimated compared to observations both at Jungnang and Gwanghwamun stations. In linear regression analysis, the slope is less than 0.8 and the bias is negative which is less than $-20W/m^2$. The estimated solar energy using MWR is more improved (i.e., deterministic coefficient (average $R^2=0.8$) and Root Mean Square Error (average $RMSE=110W/m^2$)) than when using ceilometer. The monthly cloud fraction and solar energy calculated by ceilometer is greater than 0.09 and lower than $50W/m^2$ compared to MWR. While there is a difference depending on the locations, RMSE of estimated solar radiation is large over $50W/m^2$ in July and September compared to other months. As a result, the estimation of a daily accumulated solar radiation shows the highest correlation at Gwanghwamun ($R^2=0.80$, RMSE=2.87 MJ/day) station and the lowest correlation at Gooro ($R^2=0.63$, RMSE=4.77 MJ/day) station.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.561-570
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• 2008

This study aimed to determine the effects of freeze-dried onion powder (OP) which contains rich in quercetin (22 mg/10 g) on hyperlipidemic participants. Fourteen participants (total cholesterol level in plasma $270.8{\pm}21.4mg/dL$) $40{\sim}59$ years of age who were diagnosed as hyperlipidemia by a physician at Fatima Hospital in Changwon took part in this study for 12 weeks. We investigated the anthropometric data and dietary habit by using questionnaires. Also, blood samples were collected from the patients in fasting before and after this 12 weeks intervention study. 78.6% of the patients showed interest in health diet management and weight control; however, they also showed some problems in their dietary habit (meal irregularity, food choice, calorie nutrient balance, high fat and cholesterol etc.) and life style (smoking, eating out, alcohol intake) that could have adverse effect on hyperlipidemic therapy. Most participants (85.7%) thought that OP was good for their health. The total cholesterol and LDL-cholesterol significantly decreased with OP intake. The HDL-cholesterol increased and the Atherogenic index (AI) significantly decreased. Regarding the correlations of dietary habit and life style with anthropometric and biochemical factors, the alcohol intake level was significantly correlated with the frequency of eating out and body mass index (BMI). Exercise level showed positive correlation with HDL-cholesterol and negative correlation with atherogenic index (AI). These results suggest that the intake of polyphenol rich onion may decrease the risk of hyperlipidemia by reducing cholesterol level. We consider these hypolipidemic effects of OP as a possible functional food. However, further research such as a well designed longterm clinical study with experimental and placebo groups is needed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.589-597
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• 2008

The purpose of this study is to arrange for the systematic execution of safety control in children's foods through nutrition and hygiene standard suggestions and guidelines for quality certification system in children's preferable food. Aiming to achieve this objective, the study researched the present status of children’s preferable food sold near elementary schools, elicited the hazards and problems of those foods and selected nutritional and hygienic hazard components in those foods. To suggest the standards and guidelines for quality certification in children's preferable food, the study referred to sundry records, surveyed the practical cases of relevant policies and standards at home and abroad. We studied the standard of nutrition for the quality certification in those foods for sugar, fat, sodium, and additives (tar color: red No. 2 in a ban on use, caffeine), microorganism (aflatoxin $B_1$ (${\mu}g$/kg) and pathogenic bacteria (Staphylococcus aureus, Bacillus cereus, Salmonella spp.), which are the nutrients that may hamper health when taken in a large amount, and the standard for a diet restricted to under 200 kcal per one serving size. Results of distribution of processed foods (242 samples) by nutrition standards were as follows. In case of all ‘low’ level in total sugar, total fat and sodium, 0.4% of total samples was possible to be certified, In case of all ‘medium’ level in total sugar, total fat and sodium, maximumly 22.3% of total samples was possible to be certified. In case of all medium level in nutrients and $\leq$200 kcal/serving, 17.8% of total samples was possible to be certified. Certified food types was milk products and beverages.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.4
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• pp.613-623
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• 2010

The purpose of this study was to examine parents' perceptions towards the importance and performance levels of foodservices quality at kindergartens. The questionnaire was developed to measure the thirty-one quality attributes of foodservice operations. A questionnaire survey was conducted to 500 parents and the return rates were 62.4%. The survey period was from July 15 to August 8, 2008. The parents had a high level of perception toward the need for foodservice, earning 4.46 points out of 5 point. Their perceptions of foodservice quality were examined by six dimensions of importance and performance level. While the parents gave 4 points or greater of 5 points to most quality attributes of importance level, they gave 4 points or less out of 5 points to most quality attributes of performance level. As for the importance and performance level of the quality dimensions of foodservice, parents regarded sanitation as the most important dimension. IPA showed that 'ventilation', 'sanitation of tableware' and 'sanitation of dining tables and chairs' were included as 'focus' areas. The overall satisfaction level for foodservice was 3.74 out of 5 points A higher level of satisfaction was shown at self-operated foodservice system of kindergartens. According to multiple regression analysis, 46.3% of the variance in the respondents' overall satisfaction scores was explained by factors such as food, menu and price, facilities, sanitation, atmosphere and foodservice effects.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.8
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• pp.1090-1094
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• 2008

Treatment effects of grape fruit stem extracts (GFSE) containing trans-resveratrol or fermented pollen (FP), and ethylene gas scavenging material (EGS) on the storage property of fresh jujube (Z izyphus jujuba forma hoonensis C.S. Yook) were investigated. Fresh jujubes were packed in different storage containers (PE film and Lock & Lock vessel), and treated with GFSE containing trans-resveratrol of 30 ppm or 1% FP, and EGS. The storage vessels were stored in refrigerator ($0{\pm}1^{\circ}C$) during 12 weeks, and then quality characteristics during storage period were analysed. Hardness slightly increased until 4 weeks and decreased afterward. Soluble solid ($^{\circ}Bx$) and total titratable acidity of fresh jujube slightly increased in all treatments during storage period. Vitamin C content of fresh jujube slightly decreased in all treatments during storage period. Number of microorganisms decreased until 4 weeks and increased afterward. The decay enzyme activity increased in all treatments during storage period. Storage stability was higher for PE film than Lock & Lock containers. Storage period of fresh jujube in this experiment ranges in $8{\sim}9$ weeks for maturity fruits treated with 30 ppm of GFSE and ethylene gas scavenging material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.59-65
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• 2004

Hot water-extracts prepared from Cordyceps militaris of silkworm pupa (CMP) or Cordyceps militaris of silkworm larva (CML) were tested for tumor growth inhibitory and immunomodulatory activities in ICR mice bearing sarcoma-180 cells solid tumor, and compared with those of the known compound, cordycepin, found in Cordyceps militaris. Mice were subcutaneously injected with sarcoma-180 cells, and i.p. injected with either saline (Control), 50 mg/kg or 100 mg/kg of CMP (CMP50 or CMP100, respectively), or CML (CML50 or CML100, respectively), or 1 or 2 mg/kg of cordycepin (C1 or C2, respectively) for 10 days. Mice injected with CMP50 or CMP100 showed a 47.3% or 57.6% inhibition in the solid tumor growth (P<0.05), while those injected with CML50 or CML100 exhibited a 35.5% or 37.1% reduction (p<0.05) in solid tumor size compared to the value for control mice treated with saline. Animals injected with corcycepin showed a 26∼30% inhibition in the solid tumor growth (P<0.05). Mice bearing solid tumor and injected with CMP or CML showed a significantly increased thymus weight (38∼44% increase), lymphocyte percentages of CD4+ T-cell, CD8+ T-cell, and NK-cell (63∼110% increase) in the spleen, and interleukin-2 excretion (33∼51% increase) by the isolated splenocytes compared to those in control mice (p<0.05). These results indicate that the anti-tumor activity of hot water extracts of Cordyceps militaris, raised on both silkworm pupa and silkworm larva, appears to be associated with their immunomodulatory activity, and these activities found in Cordyceps militaris are superior to those for the single compound, cordycepin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.646-652
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• 2004

With the aim of using a cosmetic material, chondroitin sulfates extracted from midduck tunics (Styela clava) and munggae tunics (Halocynthia roretzi) were examined in vitro with two cell lines for cell toxicity, collagen synthesis, cell growth and recovery ability after U.V. irradiation. Cell toxicity test with A 431 and CCD 1108Sk was able to observe high activity between 400 and 600 $\mu\textrm{g}$/m while standard chondroitin sulfate (CS) purchased from Sigma was showed at 80 $\mu\textrm{g}$/mL. Even fraction 1 and 2 collected from chondroitin sulfates originated from midduck appeared having the highest activity between 600 and 1000 $\mu\textrm{g}$/mL, but slightly lower compared to crude chondroitin sulfates from both mideduck and munggae. In cell growth examination, it was not able to find significant differences between chondroitin sulfates used. Both crude chondroitin sulfates were exhibited the highest activity for two cell lines except that of mideduck which was showed activity for CCD 1108Sk. CS, fraction 1 and 2 from midduck were not able to demonstrate a significant activity in collagen synthesis. On the contrary, crude chondroitin sulfates from both munggae and midduck were showed the highest activity at 100 and 50 $\mu\textrm{g}$/mL with only CCD 1108Sk. The recovery ability after U.V. irradiation with crude chondroitin sulfates from both munggae and midduck were showed high activity at 400 $\mu\textrm{g}$/mL with CCD 1108Sk and A 431. But there were no activity observed in fractions examined, As a consequence, the crude chondroitin sulfates from both munggae and midduck might not only be available as a cosmetic material but also useful for increasing some activity by blending properly.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.4
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• pp.723-729
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• 2004

To develop foods using dried persimmon, hot-water extracts of dried persimmons were added into strong wheat flour in the ratio of 10, 20, 30, and 40% and the quality characteristics of baked products were investigated. The proximate compositions of dried persimmons hot-water extracts were 70.37% of moisture, 1.72% of crude protein, 0.18% of crude lipids, 1.99% of crude ash and 4.37% of crude fiber, respectively. With increasing the addition of dried persimmons hot-water extracts, moisture content of the added breads was increased to 47.20% from 41.12% of non-added bread and water activity to 0.576 from 0.495. Water binding capacity of the added dried persimmons hot-water extracts rasied weight of the bread but decreased specific volume. In the hunter's color values the more dried persimmons hot-water extracts was added, the lower L vaules we, and the higher a and b values we. In the texture property, the addition of dried persimmons hot-water extracts increased hardness, gumminess and chewiness, while decreased adhesiveness and fracturability. Judging from texture, taste and overall acceptability of the product, recommended substitution level for hot-water extracts of dried persimmons in bread was 30% or less.