• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2000.09a
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• pp.201-210
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• 2000

Rock bridge in rock masses can be considered as one of several types of opening-mode fractures, and also it has been known to have a great influence on the stability of structures in rock mats. In the beginning of researching a rock bridge it used to be studied only in characteristics of its behavior, as considering resistance of material itself. However the distribution pattern of rock bridges, which can affect the stability of rock structures, is currently researched with a fracture mechanical approach in numerical studies. For investigating the effect of rock bridges on the development pattern of hydraulic fractures, the author analyzed numerically the stress state transition in rock bridges and their phenomena with a different pattern of the rock bridge distributons. From the numerical studies, a two-crack configuration could be defined to be representative of the most critical conditions for rock bridges, only when cracks are systematic and same in their length and angle. Moreover, coalescence stresses and onset of propagation stresses could be known to increase with decreasing s/L ratio or increasing d/L ratio. The effect of pre-existing crack on hydraulic fracturing was studied also in numerical models. Different to the simple hydraulic fracturing modeling in which the fractures propagated exactly parallel to the maximum remote stress, the hydraulic fractures with pre-existing cracks dial not propagate parallel to the maximum remote stress direction. These are representative of the tendency to change the hydraulic fractures direction because of the existence of pre-existing crack. Therefore s/L, d/L ratios will be identical as a function effective on hydraulic fractures propagation, that is, the $K_{I}$ vague increase with decreasing s/L ratio or increasing d/L ratio and its magnification from onset to propagation increases with decreasing s/L ratio. The scanline is a commonly used method to estimate the fracture distribution on outcrops. The data obtained from the scanline method can be applied to the evaluation of stress field in rock mass.s.

• Radiation Oncology Journal
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• v.15 no.3
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• pp.243-249
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• 1997

Purpose : In radiation therapy, NTCF is very importart indicator of selecting the optimal treatment plan. In our study, we tried to find out usefullness of NTCP in lung cancer by comparng the incidence of radiation pneumonitis with NTCP. Materials and Methods : From August 1993 to December 1994, thirty six patients with locally advanced non=small cell lung cancer were treated by concurrent chemoradiation therapy. Total dose of radiation therapy was 6480cGy (120cGy, bid) and chemotherapeutlc agents were mitomycin C. vinblastion, cisplatin (2 cycles, 4 weeks interval). We evaluated the development of raniation pneumonitis by CT scan, chest x-rar and clinical symptoms. We used grading system of South Western Oncology Group (SWOG) for radiation pneumanitis. Dose Volume Histograms (DVH) were analyzed for ipsilateral and whole lung, Non uniform DVH was translated to uniform DVH by effective volume method. With these data, we calculated NTCP for ipsilateral and whole lung. Finally we compared the clinical results to NTCP. Results : Eight of thrity six patients developed radiation pneumonitis. Of these 8 patients , 6 had grade I severity and 2 had grade II. The average NTCP value cf the patients who showed radiation pneumonitis was significantly higher than that uf the patients without pneumonitis $(66\%\;vs.\;26.4\%)$. But the results of pulmonary function test was not correlated with NTCP. Conclusion : NTCP of lung is very good indicator for selecting rival treatment planning in lung cancer. According to the results of NTCP, it may be possible to adjust target volume and optimize target dose. In the near future, we are going to anaiyze the effect of hyperfractionation and concurrent chemotherapy in addition to NTCP.

• Journal of Soil and Groundwater Environment
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• v.12 no.5
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• pp.19-32
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• 2007

In Korea, there have been various methods of estimating groundwater recharge which generally can be subdivided into three types: baseflow separation method by means of groundwater recession curve, water budget analysis based on lumped conceptual model in watershed, and water table fluctuation method (WTF) by using the data from groundwater monitoring wells. However, groundwater recharge rate shows the spatial-temporal variability due to climatic condition, land use and hydrogeological heterogeneity, so these methods have various limits to deal with these characteristics. To overcome these limitations, we present a new method of estimating recharge based on water balance components from the SWAT-MODFLOW which is an integrated surface-ground water model. Groundwater levels in the interest area close to the stream have dynamics similar to stream flow, whereas levels further upslope respond to precipitation with a delay. As these behaviours are related to the physical process of recharge, it is needed to account for the time delay in aquifer recharge once the water exits the soil profile to represent these features. In SWAT, a single linear reservoir storage module with an exponential decay weighting function is used to compute the recharge from soil to aquifer on a given day. However, this module has some limitations expressing recharge variation when the delay time is too long and transient recharge trend does not match to the groundwater table time series, the multi-reservoir storage routing module which represents more realistic time delay through vadose zone is newly suggested in this study. In this module, the parameter related to the delay time should be optimized by checking the correlation between simulated recharge and observed groundwater levels. The final step of this procedure is to compare simulated groundwater table with observed one as well as to compare simulated watershed runoff with observed one. This method is applied to Mihocheon watershed in Korea for the purpose of testing the procedure of proper estimation of spatio-temporal groundwater recharge distribution. As the newly suggested method of estimating recharge has the advantages of effectiveness of watershed model as well as the accuracy of WTF method, the estimated daily recharge rate would be an advanced quantity reflecting the heterogeneity of hydrogeology, climatic condition, land use as well as physical behaviour of water in soil layers and aquifers.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.4
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• pp.199-206
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• 2004

Factors of universal soil loss equation, USLE, and its revised version, RUSLE for Korean soils were reevaluated to estimate the national scale of soil loss based on digital soil maps. Rainfall erosivity factor, R, of 158 locations of cities and counties were spacially interpolated by the inverse distance weight method. Soil erodibility factor, K, of 1321 soil phases of 390 soil series were calculated using the data of soil survey and agri-environmental quality monitoring. Topographic factor, LS, was estimated using soil map of 1:25,000 scale with soil phase and land use type. Cover management factor, C, of major crops and support practice factor, P, were summarized by analyzing the data of lysimeter and field experiments for 27 years (1975-2001) in the National Institute of Agricultural Science and Technology. R factor varied between 2322 and 6408 MJ mm $ha^{-1}$ $yr^{-1}$ $hr^{-1}$ and the average value was 4276 MJ mm $ha^{-1}$ $yr^{-1}$ $hr^{-1}$. The average K value was evaluated as 0.027 MT hr $MJ^{-1}$ $mm^{-1}$. The highest K factor was found in paddy rice fields, 0.034 MT hr $MJ^{-1}$ $mm^{-1}$, and K factors in upland fields, grassland, and forest were 0.026, 0.019, and 0.020 MT hr $MJ^{-1}$ $mm^{-1}$, respectively. C factors of upland crops ranged from 0.06 to 0.45 and that of grassland was 0.003. P factor varied between 0.01 and 0.85.

• Journal of Food Hygiene and Safety
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• v.19 no.4
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• pp.176-184
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• 2004

This study was conducted to compare and estimate the daily PAHs dietary intake from both home-cooking and dining-out, through approach of model diet used in exposure assessment of food contaminants. Food commodities reflecting in model diet were selected from the KHIDI report and were analysed in cooked or uncooked edible forms using HPLC-Fluorscence Detector. The PAHs dietary intake comparison between home-cooking and dining-out was based on one meal intake suggested in model diet and PAHs dietary intake was estimated by using food consumption rate and body weight of the Korean adult group. The daily PAHs dietary intake was calculated by permutation and combination method with assumption that a person consumed 2 meals from home-cooking menu and 1 meal from dining-out menu. The total PAHs levels in 36 food commodities with 200 samples were ranged from 2.00 ug/kg to 141.28 ug/kg and a food showing the highest PAHs level was the stir-fried anchovy. The $TEQ_{BaP}$ levels of PAHs were calculated using benzo(a)pyrene equivalents individual congener level and corresponding TEF value and the $TEQ_{BaP}$ level were ranged from $0.03\;ugTEQ{BaP}$ to $1.31\;ugTEQ_{BaP}$ and a food showing the highest $TEQ_{BaP}$ level was the hamburger. The PAHs dietary intakes per one meal from home-cooking and dining-out were $2.4\times10^{-3}\;ugTEQ_{BaP}/kg/meal\;and\;4.0\times10^{-3}\;ugTEQ_{BaP}/kg/meal$, respectively. This data showed the PAHs dietary intake from dining-out was about 1.7 times higher than from the home-cooking. The daily PAHs dietary intakes of general Korean adult having two meals from home-cooking and one meal from dining-out per a day were ranged between $8.0\times10^{-3}\~9.7\times10^{-3}\;ugTEQ_{BaP}/gg/day$ and mean value as $8.9\times10^{-3}\~9.7\times10^{-3}\;ugTEQ_{BaP}/gg/day$.

• The Korean Journal of Ecology
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• v.23 no.5
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• pp.397-406
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• 2000

In order to clarify the ecophysiological characteristics of Chenopodiaceae which widely distribute on saline and arid habitats, we collected 10 chenopodiaceous plant species, examined their inorganic and organic solute patterns, and confirmed several common physiological characteristics. In spite of high soil Ca/sup 2＋/ contents, chenopodiaceous plants had a little water-soluble Ca within cells, but contained high contents of acid-soluble Ca particularly as a result of Ca-oxalate formation. These plant species also showed accumulation of inorganic ions such as K/sup ＋/, NO₃/sup －/ and Cl/sup －/, and Na/sup ＋/especially in saline habitats instead of K/sup ＋/ Meanwhile, with respect to nitrogen metabolism they retained high N contents in leaves, but showed very low amino acid contents. Additionally, they contained very little proline known to act as a cytoplasmic osmolyte. To ascertain whether this physiological characteristics in the field also can be found under controlled conditions, 7 chenopodiaceous plants (Atriplex gmelini, Corispermum stauntonii, Salicornia herbacea, Suaeda aspayagoides, Suaeda japonica, Chenopodium album var. centrorubrum, C. serotinum) were selected and cultivated under salt treatments. As well as field-grown plants, selected plant species showed similar solute pattern in growth experiment. In summary, the family of Chenopodiaceae represents the following physiological properties; high storage capacity for inorganic ions (especially alkali cations, nitrate and chloride), oxalate synthesis to maintain lower soluble Ca contents within cytoplasm, and low contents of amino acids. In addition to some characteristics mentioned above, the physiological plasticities of Chenopodiaceae which can properly regulate their ion and solute pattern according to soil conditions may enable its representative to grow in dry sand dune and salt marsh habitats.

• Culinary science and hospitality research
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• v.16 no.3
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• pp.268-277
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• 2010

Gochujang and red pepper powder are the representative condiments in Korea. This study examines gochujang sauces for tteokbokgi by hot taste degree(4 levels) and then evaluated the quality and sensory characteristics of gochujang sauces to provide the basic information for industrialization of gochujang sauce. Moisture content of gochujang sauce 1 was the highest (53.90%). Moisture content became decreased against hot taste. pH range of gochujang sauce was 5.50~5.84. pH values of sauces increased in accordance with hot taste. In the Brix contents, sauce 3 was the highest(46.73%), but the sauce 1 was a little low. Viscosity of sauce 4 was 237.93 cp and others became decreased in accordance with hot taste. In the lightness(L value), sauce 2 was the highest(24.89). Capsaicin content of sauce 4 was 27.00 mg/100 g while sauce 1 was 22.97 mg/100 g. In sensory evaluation, color of sauce 4 was darkest. In hot taste, sauce 1 was evaluated as less hot while sauce 4 as most hot. Overall acceptability score range of sauce 2, 3, 4 was 4.95~5.50 which was higher than sauce 1. The result of a research conducted to undergraduate students showed that they preferred hot taste gochujang sauce. Consequently, customers should be more satisfied with sauce products they chose when provided with those by hot taste degree. In the future, more studies are required about the degree of hot taste for the successful industrialization and globalization of hot pepper and gochujang.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.4
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• pp.644-649
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• 2013

This study was conducted to determine the intake and satisfaction levels of Busan local foods in Japanese tourists visiting Busan. The degree of satisfaction with Busan foods and services in restaurants was evaluated. What these tourists wanted to eat after touring Busan was also determined. The subjects consisted of 100 Japanese tourists visiting Busan. Women (including housewives), highly educated people, and people who visited more than four times were predominant in number among the Japanese tourists. Busan local foods eaten during touring were: Dongrae Pajeon (29%), Sengsunhoe (21%), Daejikukbap (10%) and Haemultang (10%). Tourists wanted to taste local foods and answered that eating local foods during the tour was important. A variety of menu items earned a high score of 3.8 (from a highest possible score of 5.0) and various dessert items received a low score of 2.7 for satisfaction with Busan foods. In general, the satisfaction level for Busan foods was low. Tourists responded that they wanted to eat Bulgogi, Pajeon, Bibimbap, Sengsunhoe, and Kimchi jjigae in that order if they revisit Busan, indicating their preference for general Korean foods rather than Busan local foods. From all of the activities included in touring Busan, foods received the highest points (51%) in terms of attraction. As fifty four percent of subjects answered that they wanted to revisit Busan. Busan city needs to prepare tourist restaurants for Bulgogi, Bibimbap, Pajeon, and seafoods (including Sengsunhoe). They must also improve Busan local foods and restaurant services in order to attract and satisfy the Japanese tourists industry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.9
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• pp.1106-1113
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• 2017

The objective of this study was to determine the quality characteristics of fried yakgwa and baked yakgwa prepared with different amounts of P. frutescens powder. Moisture contents of fried yakgwa were 7.05%, and moisture content of baked yakgwa with different amounts of P. frutescens powder were 12.42~10.44% and decreased with higher amount of P. frutescens powder. This result can be attributed to loss of water in yakgwa in the course of the fried process. Although the degree of expansion of baked yakgwa was lower than that of fried yakgwa, size and shape of yakgwa were maintained. Yakgwa is appropriate as a cookie type product. Crude lipid contents of fried yakgwa were higher than those of baked yakgwa due to the exchange reaction of water and fat during the fried process. Energy of fried yakgwa was 501 kcal and was higher than that of baked yakgwa with different amounts of P. frutescens powder. This greatly affected the fat content of each sample. Energy of baked yakgwa increased with higher amount of P. frutescens powder due to the characteristics of the ingredients or jasoyeop. For chromaticity determination, L values of fried yakgwa were lower, but a, and b values were higher than those of baked yakgwa, and L, a, and b values decreased when P. frutescens powder increased. Texture measurement showed that hardness, cohesiveness, chewiness, gumminess increased with higher amounts of P. frutescens powder, whereas springiness decreased. The antioxidant activities of fried yakgwa measured based on DPPH scavenging activity were higher than those of baked yakgwa with 0%~0.2% P. frutescens powder and lower than those of baked yakgwa with 0.3%~0.4% P. frutescens powder. In the sensory evaluation, baked yakgwa with 0.1% addition of P. frutescens powder showed the highest preference in terms of overall acceptance, and 0% addition of P. frutescens powder showed the highest preference in terms of color and flavor. These results suggest that P. frutescens powder may be a useful ingredient in baked yakgwa to improve quality and sensory properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.270-278
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• 1995

This report described on the soluble, insoluble, and total dietary fiber level depending on the harvesting seasons and habitats in 9 species of marine algae. Total dietary fiber contents were comprised $25.4-38.1\%$ (dry basis) in green laver and $35.4-43.8\%$in sea staghorn of green algae, $34.2-48.8\%$ in sea mustard, $37.5-47.8\%$ in seaweed fusiforme, $42.9-71.3\%$ in gulf weed, and $37.1-45.1\%$ in sea tangle of brown algae, and $31.3-40.5\%$ in laver, $51.5-60.4\%$ in seaweed dilatata, and $57.1-65.8\%$ in seaweed furcata of red algae. Relatively high levels of both soluble and insoluble dietary fibers were found in seaweed furcata and gulf weed. The ratio of soluble dietary fiber to total dietary fiber was the highest in green laver $(43.7-64.8\%)$, sea mustard $(17.5-31.3\%)$, and seaweed furcata $(44.7-63.2\%)$ in their respective groups. The highest level of algal polysaccharides was confirmed to be an alkali-soluble alginic acid $(9.0-15.1\%)$ in whole brown algae, porphyran$(5.8\%)$ in laver, agar $(20.0\%)$ in seaweed furcata, and carrageenan $(23.8\%)$ in seaweed dilatata of red algae.