• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.510-523
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• 2020

This study analyzed groundwater quality in hydroponic cultivation facilities. Through this study, the possibility of groundwater use was evaluated according to the quality of the groundwater for hydroponic cultivation facilities. Good groundwater quality, on average, is pH 6.61, EC 0.27 dS/m, NO3-N 7.64 mg/L, NH4+-N 0.80 mg/L, PO4-P 0.09 mg/L, K+ 6.26 mg/L, Ca2+ 18.57 mg/L, Mg2+ 4.38 mg/L, Na+ 20.85 mg/L, etc. All of these satisfy the water quality standard for raw water in nutrient cultivation. But in the case of farmers experiencing problems with groundwater quality, most of the items exceeded the water quality standard. As a result of the analysis, it was judged that purifying groundwater of unsuitable quality for crop cultivation, and using it as raw water, was effective in terms of water quality and soil purification. If an agricultural water purification system is constructed based on the results of this study, it is judged that the design will be easy because the items to be treated can be estimated. If a purification system is established, it can use groundwater directly in the facility and for horticulture. These study results will be available for use in sustainable agriculture and environments.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.1
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• pp.38-49
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• 1986

In order to improve effectiveness of rhizobia-legume symbiotic nitrogen fixation, ecological and physiological characteristics of indigenous rhizobia distributed in Korea soil, that is, the effects of soybean cultivation, physico-chemical properties and climate on the population of indigenous rhizobia and other soil microbes were investigated. The results were summarized as follows: The population of indigenous rhizobia were ranged from $5.1{\times}10^4$ cells to $196.8{\times}10^4$ cells per gram of soil in soybean cultivated soils but from $1.6{\times}10^4$ cells to $78.6{\times}10^4$ cells per gram of soil in soybean un-cultivated soils sampled from 9 different agro-climate zone. The highest population was observed in a soybean cultivated loamy soil from southern part of Korea. The content of available phosphate, exchangeable Ca, Mg, Cu, and B in soil were positively correlated but active Fe, exchangeable Al, Na, and $SO_4$ were inversely correlated to the population of indigenous rhizobia. The inverse relationship was observed between the number of indigenous rhizobia and actinomycetes.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.590-603
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• 2006

Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.6
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• pp.499-512
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• 2016

The boundary reaction method(BRM) is a substructure time domain method, it removes global iterations between frequency and time domain analyses commonly required in the hybrid approaches, so that it operates as a two-step uncoupled method. The BRM offers a two-step method as follows: (1) the calculation of boundary reaction forces in the frequency domain on an interface of linear and nonlinear regions, (2) solving the wave radiation problem subjected to the boundary reaction forces in the time domain. In the time domain analysis, the near-field soil is modeled to simulate the wave radiation problem. This paper evaluates the performance of the BRM according to modeling extent of near-field soil for the nonlinear SSI analysis of base-isolated NPP structure. For this purpose, parametric studies are performed using equivalent linear SSI problems. The accuracy of the BRM solution is evaluated by comparing the BRM solution with that of conventional SSI seismic technique. The numerical results show that the soil condition affects the modeling range of near-field soil for the BRM analysis as well as the size of the basemat. Finally, the BRM is applied for the nonlinear SSI analysis of a base-isolated NPP structure to demonstrate the accuracy and effectiveness of the method.

• Journal of Nutrition and Health
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• v.7 no.2
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• pp.53-63
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• 1974

For the elucidation of the nutritional status of residences of apartments located in various areas in Seoul city, the food and nutrition survey was undertaken by the graduate students from Department of Food & Nutrition, Ewha Womans University in 1973. The socioeconomic stratification was mainly considered for the selection of sample apartments included in this study. Hangang Mansion, KIST, Munwhachon & Bukahyun apts were selected in this respect. A. Common living circumstances. Through the questionaries, author concluded nutritional concept on everyday food life as follows; 1. Higher income seems less effective in everyday food life on the nutritional view point than higher education does. 2. It needs to be urgently improved to be accustomed to use exact measuring concept of foods when they cook. 3. It needs to be improved to serve meals for individual portion at meal table, because the portion control at meal table will effect to national food policy. B. Nutrition Survey. Average daily calroie intake was the highest in Hangang Mansion and lowest in Bukahyun apt., in accordance with their economic living standard, but most of their calorie intakes were lower than the R.D.A. (3000ca1 for male, 2200 Cal for female). But the composition ratio of the total calorie intake was near to the ideal, carbohydrate 60%, protein 15%, fat 25%. Although there were differences in their economic living situations in urban area, most people ingested relatively good quality and large amounts of protein and fat. Vitamin A and Niacine intake exceeded the R.D.A., but the intake of Ca, Thiamine, Riboflavin, Ascorbic Acid were far less than that of R.D.A. C. food Intake. Amounts of total daily food intake were highest in Bukahyun apt. and lowest in Hangang Mansion. These showed adverse aspects to the total calorie intakes and their income levels. The ratio of cereals, $40%{\sim}50%$ of the total food intake, was higher than any other kinds of foods in all apartments. Among the other foods except cereals, there represented the highest level of meats in Hangang Mansion and KIST apt., while intake of Kimchies were highest in Munwhachon and Bukahyun apt. In the case of vegetables and fruits intake, the ratio of them in Hangang Mansion and KIST apt. were high, on the other hand the ratio of starchy roots appeared lowest in Hangang Mansion. For the main sources of protein, meats were ingested in Hangang Mansion and KIST apt., meats and fishery were used in Munwhachon apt., and beans were eaten highly in their meals in Bukahyun apt. These food contents and distributions showed the significant differences not only their economic classes but also regional characteristics.

• Journal of the East Asian Society of Dietary Life
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• v.12 no.2
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• pp.107-122
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• 2002

The purpose of this study was to develop menus for daily intake of 25g soybean protein and to analyse nutrients of these foods. Analytical values were compared to the theoretical one using the flood composition table and recommended dietary allowances for Koreans (7th revision). The results are as follows. 1. Soybean curd residue stew, Soybean curd, Kimchi saute, and hard boiled soybean and lotus root were selected for the menu for January, of which the content of soy bean protein(SBP) was 33.1g, soybean stew, soybean curd and soybean sprout saute, and Italian deep fried soybean curd were fur February, of which the content of SBP was 35.0g. The content of SBP in soybean paste soup with soybean curd, fried soybean curd and fried soybean curd roll, the menu for March, was 24.9g. That of April were soybean curd gratin with soymilk, soybean curd and ham with garlic dressing and the content of SBP was 26.3g. That of May were soybean porridge, soybean flour cake with honey (Dasik), soybean sprout soup and the content of SBP was 26.7g. That of June were soymilk, pan-fried soybean curd, steamed soybean curd with chicken and the content of SBP was 28.4g. That of July were noodle with soymilk, mapatofu, soybean curd salad and the content of SBP was 24.7g. That of August were soybean sprout with mustard dressing, Tossed green pepper with raw soybean flour, Tofu and Kimchi stew, soybean curd steak and the content of SBP was 26.2g. That of September were Chinese cabbage soup with raw soybean flour, sweet and sour tofu and the content of SBP was 23.2g. That of Oct. were Fermented soybean stew, soybean pan cake and the content of SBP was 24.3g. That of November were not-pressed soybean curd casserole, pan-fried mashed soybean curd with egg, stir frying deep-fried soybean curd with vegetables and the content of SBP was 22.4g. That of December were soybean curd and mushroom casserole, fried soybean curd and vegetables, hard boiled soybean curd and the content of SBP was 28.9g. 2. The ratio of the analytical value over theoretical value (A/B%) of one serving in kcal, carbohydrate, protein, fat ash and dietary fiber were 57.7~107.7% 42.9~131.9%, 79.2~118.3%, 54.5~ 100%, 40.7~80.8% and 42.1~113.2%, respectively.

• Proceedings of the Technology Innovation Conference
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• 1997.07a
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• pp.222-223
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• 1997

By analyzing the successful innovation case of potato microtuber mass production technology, a representative case of technology-push type creative innovation in an imitation oriented research culture, this paper attempts to figure out conceptual model of creative innovation that is initiated by the public laboratories in catching-up country, Stages of creative innovation can be divided into the internal R&D stage and the external commercialization stage. Success of the internal R&D stage depended on autonomy to secure creative research idea and commitment of individual researchers. Psychological pressure evoked from sportlights of mass media and commitment of sponsor increased the intensity of research efforts of the researcher Recognition of research problem and its significance was intensified by site visits of agricultural fields, and the recognized higher impacts of expected research results and knowledge creation achieved were a fundamental source of self-motivation. In the stage of commercialization stage, various legal, socio-economic, and psychological barriers were confronted. In a catching-up country lacking of experiences of creative innovation, creative innovation process can be regarded as a barrier elimination and cultural revolution process. Among the barriers, psychological refusal of farmers to corn-sized potato seeds was critical, which finally enforced to further researches to enlarge the size of potato seeds. In addition, the researcher has concentrated his research efforts in one specialized research area by getting a series of similar research project funds rather than diversification. It was lucky for him to have a chance to carry out a series of similar researches in one research area during the last 10 years. In getting research funds from government and private companies continuously in one research area, both internal and external promoters played significant roles.

• Korean Journal of Environmental Agriculture
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• v.2 no.2
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• pp.98-102
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• 1983

The hydrogen fluoride gas generated from making the cement hardener injured the plants growing at the neighbour field. This investigation was conducted on sample analysis of hydrogen fluoride gas damage plants which included the ratios of destroyed leaves, damage symptoms, and nutrient elements in paddy rice and weeds. The results obtained were as follows; 1) The ratio of destroyed leaves at near HF source was very high reaching about 95% at 100m, 65% at 500m, 5% at 2㎞, respectively. 2) The necrosis was the characteristic symptom of fluoride injury on rice plant and occurred predominantly at the tip and margins of damage leaf. It developed along the tip and margins of leaves with a dull, gray-green, water soaked discoloration. 3) The fluorine content of tip and margins of damaged rice leaves were 1,600 ppm, 3 to 20 times higher than that of center part and it ranged from 130 to 242.5 ppm in weed leaves, but from 10 to 15 ppm in normal weed leaves. 4) The contents of calcium, potassium, silicon, iron and manganese were higher in tip and margins than in the center of rice damage leaves. 5) The Cocculus trilolous. D.C was the most resistant plant to HF gas than any other plant growing in this site, while wild berry and aralia tree belong to most sensitive plant group.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.199-208
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• 1977

Activities of various hydrolytic enzymes produced by three plant pathogenic fungi, Sclerotium rolfsii Sacc., Sclerotinia sclerotiorum (Lieb.) deBary and Helminthosporium sigmoideum var. irregulare Crallery et Tullius, were measured. Activties and amounts of the enzymes in mycelia, cultural filtrates, and sclerotia(except of sclerotia of H. sigmoideum var. irregulare) were estimated at various pH levels in order to find out optimal pH for their enzymatic activities. Enzymes such as cellulase (ex), invertase, xylanase, $\beta-amylase$, polymethylgalacturonase, polygalacturonase, phosphatase and protease were estimated. Culture solution for production of enzymes was prepared by adding of 10g, D-glucose, 1.3g $NH_4NO_3,\; 0.5g\; MgSO_4,\;7H_2O,\; and\; 1.0g\; KH_2PO_4$ into 1 liter of potato decoction plus 2ml of micro element solution consisting of 0.2mg. Fe, 0.2mg Zn, and 0.1mg Mn as the sulphates into 1 liter of distilled water. All tested mycelia and cultural filtrates were obtained from the cultures incubarted in previous solution for ten days at $25^{\circ}C$, and sclerotia were harvested from PDA plates of 3. days old, The crude enzyme solutions were prepared according to the method of Miyazaki etal. Ten days after incubation, activities of Cx produced by Scl. sclerotiorum were higher than those of the other fung and each of Cx from three fungi showed different pH optima, such as S. rolfsii and Scl. schlerotiorum in acid side (around pH 3.0), H. sigmoideum var. irregulare in neutral side (around pH 6.3). Invertase activities of S. rolfsii were 20 times higher than those of the other fungi in all samples. All tested fungi, however, showed no significant difference between the enzymatic activities of their cultural filtrate and mycelia and the activities in sclerotia of S. rolfsii and Scl. sclerotiorum were hardly recognized. There were multiple peaks on the xylanase activity curves of three fungi in terms of pH values. High activities of the xylanase were revealed in sclerotia of S. rolfsii and Scl. sclerotiorum, and in mycelia of H. sigmoideum var. irregulare. The highest activities of $\beta-amylase$ were shown both in mycelia and cultural filtrate of H. sigmoideum var. irregulae among the tested fungi, and their optimal pH was 6.2 in both mycelia and cultural filtrate. In the S. rofsii and Sel. sclerotiorum, however, the activities of cultural filtrates were higher than those of the other fungi, and optimal pH was 3.0 and 6.2 for cultural filtrate and both mycelia and sclerotia, respectively. Activities of PMG were high in cultural filtrates of all tested fungi, especially in Scl. sclerotiorum and H. sigmoideum var. irregulare. Mycelia of themalso showed the considerable activities. Optimal pH for enzymatic activities were variable with thekind of fungi or with the samples measured. The highest activities of PG were presented by mycelia of S. rolfsii and Scl. sclerotiorum. $9.l\mu /min.\; and\; 9.5\mu g/min.$, respectively. Optimal pH for activity of PG in mycelia was around 4.5 in S. rolfsii and around 3.0 in Scl. sclerotiorum. Phosphatase of S. rolfsii and Scl. sclerotiorum was more active in acid side (optimal PH3. 5) and that of H. sigmoideum var. irregulare showed one peak each in acid, neutral and alkaline side. But the highest peak was at pH 9.5. Protease of all tested fungi was more active at pH 10.0, especially that of the cultural filtrate of H. sigmoideum var. irregualre.

• Food Science and Preservation
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• v.8 no.4
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• pp.419-426
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• 2001

This study was carried out to develope a convenient instant spiced Toha-jeot. Toha-jeot was manufactured by five samples; 8%, 10%, 13% 23% sodium chloride and a conventional type soy sauce. The Toha-jeot was refrigerated at 4$\pm$1$\^{C}$ for 3 months and then boiled glutinous rice, red pepper powder, chopped garlic and ginger were added, and the spiced Toha-jeot was fermented at 4$\pm$1$\^{C}$ for 2 months, was freeze-dried at a condition of 40$\^{C}$, vacuum 100∼200 millitor millitorr and then packed in vacuum. It is called freeze-dried instant spiced Toha-jeot (FIST). Changes in the components and quality of refrigerated spiced Toha-jeot (RST) and FIST were investigated for 30day. The moisture content of RST was 53.79∼58.91%. Among the mineral constituents of RST, Na and Ca were dominantly occupying. Water activity of FIST was 0.28-0.39 while that of RST was 0.87-0.92. TBA value of FIST was lower than that of RST. Acidity, VBN (volatile basic nitrogen) and TBA(thiobarbituric acid) of the FIST and RST increased slightly, whereas pH decreased. The major components of fatty acids in FIST and RST were analysed into a feater amount of linoleic acid (Cl8:2), palmitic acid (Cl6:1), oleic acid (Cl8:1), linolenic acid (Cl8:3), EPA (C2O:5) and stearic acid(Cl8:0). In sensory evaluation, the RST had higher scores in color and taste and the FIST in chewiness and flavor. The qualitative characteristics and sensory evaluation of FIST and RST were similar.