• Journal of Korea Water Resources Association
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• v.36 no.6
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• pp.1069-1082
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• 2003

The Cheongdocheon has the reaches under reduction of stream flow. We analysed the cause of the reduction. We investigated the current status of facilities for agricultural water use. We also compared the discharge measurements with the results from the continuous simulation of watershed runoff The satellite image was a tool to find some reaches of stream flow reduction under doubt. Agricultural reservoirs block up the stream and water does not flow over the reservoirs except by storm. They also discharge water through diversion channels and the water diverted does not flow through the natural stream. Farmers directly take water from the stream by weirs. The infiltration gallery of water below the stream ground makes the reach dryness perfect in Kamakchon. These are causes of the stream flow reduction. The discharge measurements are less than the simulation results of watershed runoff, and we guess that the reaches investigated have dried. We found the reaches of stream flow reduction that were under doubt from some KOMPSAT satellite images with the resolution of 6.6 m. Then, we confirmed the reduction of stream flow by a field investigation. All the above reaches have infiltration galleries of water below the stream ground. The research results are a case study on the cause analysis on the reduction of stream flow. One can obtain the KOMPSAT image for a low price and can get prior information to find the doubtful reach of stream flow reduction.

• Journal of Korea Water Resources Association
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• v.45 no.8
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• pp.839-851
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• 2012

When we evaluate the water supply capacity of a river basin, it is a common practice to gradually increase the water demand and check if the water demands are met. This practice is not only used in the simulation approach, but also in the optimization approach. However, this trial and error approach is a tedious task. Hence, we propose a two-phase method. In the first phase, by assuming that the decision maker has complete information on inflow data, we use a goal programming model that can generate the maximum water supply capacity at one time. In the second phase, we simulate the real-time operation for the critical period by utilizing the water supply capacity given by the goal programming model under the condition that there is no foresight of inflow. We applied the two-phase method to the Geum-River basin, where multi-purpose weirs were newly constructed. By comparing the results of the goal programming model with those of the real-time simulation model we could comprehend and estimate the effect of perfect inflow data on the water supply capacity.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.46-49
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• 2003

Paddy and milled rice quality, milling characteristics, energy consumption of milling process were investigated using Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo varieties. Thousand grains weights of the varieties dried to 15% moisture content were 22.92-28.60 g, with Dasanbyeo being the heaviest. Optimum clearance of rubber roller for obtaining maximum dehulling recovery was 30% of each rice variety thickness. At that time, perfect brown rice ratios of Dasanbyeo, Ansanbyeo, Hwaseongbyeo, Ilpumbyeo, and Donganbyeo were 95.24%, 98.86%, 95.97%, 97.75%, and 97.31%, respectively, and showed no significant differences among varieties. Ratios of removed rice bran after two times milling ranged 70.93-91.38%, with Dasanbyeo showing the highest ratio, and the average head rice ratio was 92.87%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4780-4786
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• 2010

This study focuses on the creation new jobs since it is considered as the national purpose recently. As this phenomenon regarded, this study is purposed to explore the effects of social network on entrepreneurial intentions and new venture. To promote an empirical analysis, the sample survey based on 208 domestic nascent entrepreneurs are collected and multiple regression analysis and mediated regression analysis are used. The results of an empirical analysis are as follow. First, the finding shows that social network of the strong ties and the week ties positively affect on entrepreneurial intentions. The strong ties more influence on entrepreneurial intentions. On the other hand, the week ties which are based on substantial business knowledge, information, and technology more affect on entrepreneurship. Second, entrepreneurial intentions play a role in the partial mediation effect between the strong ties and entrepreneurship, and the perfect mediation effect is indicated by between the week ties and entrepreneurship. The results suggest that nascent entrepreneurs have a lack of capital during business start-up period. As this regard, they tend to achieve related entrepreneurship resources through the strong ties such as family, relatives, and friends. Moreover, it is suggested that the potential nascent entrepreneurs should be aware of necessity of technological and economical support so that it can establish various social network. Furthermore, it encourages entrepreneurial intentions, fosters entrepreneurship, and indicates the direction of entrepreneurship through practical suggestions. it is expected that moderating effect of gender on nascent entrepreneurs and non nascent entrepreneurs leads to useful results for the future.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.440-445
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• 2010

This study was carried out to investigate the toxicities of five registered insecticides to the Lycorma delicatula nymphs and adults. Insecticidal activities were evaluated by testing systemic and residual effects in the laboratory, and control efficacy in the vineyard. For the 3rd nymphal instars and adults, etofenprox+diazinon, chlorpyrifos, etofenprox, dinotefuran and imidacloprid showed perfect insecticidal activity. The systemic effects of dinotefuran and etofenprox+diazinon on grape roots at half concentration were showed the adult mortality of 82.2% and 84.4%, respectively. Chlorpyrifos at recommended concentration was showed mortality of 86.0%. The leaf systemic effects at recommended and half concentrations of all insecticides except dinotefuran were lower than 65% but the mortality at double concentration of chlorpyrifos, dinotefuran, etofenprox were more than 82%. The residual effect between etofenprox+diazinon and dinotefuran at recommended and double concentrations were 100% at 14 days after treatment, the other insecticides have low efficacy. All the four insecticides showed 87% control value on nymphs in the field test and adults appeared more than 96% control value st and adinotefuran, etofenprox+diazinon, however, the other insecticides decreased to 59.1 % and 61.2%. Therefore, dinotefuran and etofenprox+diazinon showing high systemic effects to roots and long residual effects to leafs have high control efficacies.

• Restorative Dentistry and Endodontics
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• v.16 no.2
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• pp.43-61
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• 1991

Present - day inlay casting procedures have been developed for more than 100 years and experimentation has focused on the perfect adaptation to the cavity preparation. Marginal adaptation is considered to be an important indicator of the acceptability of the cast restotration, especially on the gingival margin. The purpose of this study was to evaluate the effects of a dissecting microscope and burnishing on vertical discrepancies, horizontal discrepancies, and cement thicknesson master die. Extracted premolars were prepared for class II gold inlays and master dies were made with conventional techniques. The experiments consisted of 4 groups. Group 1 : unaided eye, no burnishing on master die. Group 2 : unaided eye, burnishing on master die. Group 3 : microscope, no burnishing on master die. Group 4 : microscope, burnishing on master die. Cemented inlays were embedded in the hard resin and sectioned with microcutter through the gingival margins. The sectioned surfaces were polished with emery paper and finally with aluminum oxide powders. The results of the experiments were measured for vertical discrepancies, horizontal discrepancied and cement thickness under the scanning electron microscpe at the beveled gingival margin. The results of the study were summarized as follows. 1. Group 1 showed the vertical discrepancies of $81.6{\mu}m({\pm}48.6{\mu}m)$, horizontal discrepancies of $60.1{\mu}m({\pm}41.1{\mu}m)$, and cement thickness of $59.6{\mu}m({\pm}24.6{\mu}m)$. 2. Group 2 showed the vertical discrepancies of $78.6{\mu}m({\pm}30.9{\mu}m)$, horizontal discrepancies of $36.9{\mu}m({\pm}20.7{\mu}m)$, and cement thickness of $54.0{\mu}m({\pm}21.6{\mu}m)$. 3. Group 3 showed the vertical discrepancies of $57.5{\mu}m({\pm}26.4{\mu}m)$, horizontal discrepancies of $28.4{\mu}m({\pm}17.5{\mu}m)$, and cement thickness of $37.2{\mu}m({\pm}17.4{\mu}m)$. 4. Group 4 showed the vertical discrepancies of $56.7{\mu}m({\pm}35.0{\mu}m)$, horizontal discrepancies of $31.8{\mu}m({\pm}24.2{\mu}m)$, and cement thickness of $45.6{\mu}m({\pm}19.8{\mu}m)$. 5. Vertical discrepancies were not significantly different at any groups(p>.050). 6. Microscope groups(Group 3, 4) showed significantly improved horizontal marginal adaptation (p<.050). 7. Although cement thickness showed the subset of Group 3. 4, 2 and Group 4, 2, 1. Group 3 showed significantly smaller thickness than Group l(p<.050). 8. Finishing and polishing by means of a microscope produced significantly smaller discrepancies than doing so with the unaided eye(p<.050).

• Journal of Periodontal and Implant Science
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• v.41 no.1
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• pp.10-16
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• 2011

Purpose: Avulsed tooth can be completely recovered, if sound periodontal ligament (PDL) of tooth is maintained. Although a lot of storage solutions have been explored for the better storage of avulsed tooth, there is a shortcoming that the preservation time is much short. On the other hand, there has been studies that (-)-epigallocatechin-3-gallate (EGCG), the most abundant polyphenol in green tea, which is related to the anti inflammatory, antioxygenic, and antibacterial effects, allows the successful preservations of tissues and cells. This study evaluated the effect of EGCG on avulsed-teeth preservation of Beagle dogs for a period of time. Methods: The atraumatically extracted teeth of Beagle dogs were washed and preserved with 0/10/$100\;{\mu}M$ of EGCG at the time of immediate, period 1 (4 days in EGCG-contained media and additional 1 day in EGCG-free media), period 2 (8 days in EGCG-contained media and additional 2 days in EGCG-free media) and period 3 (12 days in EGCG-contained media and additional 2 days in EGCG-free media). Then, the cell viabilities of preserved teeth was calculated by dividing optical density (OD) of 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay with OD of eosin assay to eliminate the measurement errors caused by the different tissue volumes. Results: From the results, the immediately analyzed group presented the highest cell viability, and the rate of living cells on teeth surface decreased dependent on the preservation period. However, the $100\;{\mu}M$ of EGCG-treated group showed statistically significant positive cell activity than EGCG-free groups throughout preservation periods. Conclusions: Our findings showed that $100\;{\mu}M$ EGCG could maintain PDL cell viability of extracted tooth. These results suggest that although EGCG could not be a perfect additive for tooth preservation, it is able to postpone the period of tooth storage. However, further in-depth studies are required for more plausible use of EGCG.

• Fire Science and Engineering
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• v.13 no.4
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• pp.38-55
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• 1999

In order practically to use fire-defective glazing materials for the compartment wall where a fire-protection rating is mandated, there have been many trials internationally, This research focuses on a feasibility that, if certain water film covered all surface of glass, the glazing system can endure without breaking out under the compartment fire. First of all, a water film spray system was specially designed to wet the entire surface of the glass and also to have tiny small amount of water rebounded from the surface after emitted from nozzles. After this system has proven to have perfect performance, small-scale tests were done to find out if the water film covered glazing system react to the high temperature curve in a small furnace room. Finally, on basis of the obtained data, full-scale experiments were done so that water-film covered glazing system can pass the Korean Standard (KS) test for fire resistance, KS F2257.

• Archives of design research
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• no.18
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• pp.165-174
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• 1996

In the I950s the German firm Braun began to pursue a policy of uncompromising modem design for products aimed at the upper reaches of the market. Dr. Fritz Eichler as a head of design with Hans Gugelot and Otl Aicher in the Graduate School VIm developed the guide line of Braun Design strategy as the foundation of the corporate identity programme. In 1955 Dieter Rams joined the staff, and was largely responsible for establishing the formal characteristics of Braun Design and its further development. In the mid-1950s complete product programme of the firm Braun began to be re-designed, and these undoubtedly hit the market. New design line of the firm Braun, was an exclusive avantgarde movement at that time, which became to be the epitome of the idea of an objectifiable "Good Form". By the result in the 60s and 70s, when Braun product program was completely re-designed to the new line, Braun Design had a decisive influence on the design scene of the world. Braun Design is essentially functional and concrete, which depends on perfect fulfillment of purpose, precision, safety, durability, the quality of the product and, more recently, environmental compatibility is similarly balanced and unified approach, eliminating every unnecessary detail and concentrating on ordering essential elements. elements.

• Research in Community and Public Health Nursing
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• v.7 no.2
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• pp.410-419
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• 1996

This study was reviewed from 1000 articles related to family planning from 1970 to 1990 and 20 articles associated with natural family planning from 1980 until the present. The purpose of natural family planning(NFP) is to identify the time ovulation of women themselves, to have intercourse with periodic abstinence, and to deliver a healthy child. The ultimate goal of NFP is to promote the family's health. The NFP method is described as periodic abstinence of intercourse to avoid pregnancy by identifying the ovulation time in the menstration cycle. Clinical symptoms and signs of reflection underlying changes in Estrogen and Progesterone are the change of basal body temperature, the change of cervical mucus and cervix, abdominal pain and breast tenderness. The types of NFP are the calender rthythm method, basal body temperature methods, cervical mucus method, symptothermal method, cyclo-thermal method and home based ovulation test kits. Recently the cyclo-thermal method involved. It is calendar rhythm method applied to B.B.T. For the cervical mucus method, when the estrogen level in the blood concentration is increased, the mucus begins to excrete, the amount of moist mucus increases while the mucus is clear, slippery, and smooth. For 3 days, this timing can be considered contraception. Fertility is at a maximum on the day mucus appears, abstinence for 3 days is a type of contraception. Sexual intercourse on a maximum day of mucus maximizes pregnancy potential. But, the contraception depends on the practice of a perfect rule. For basal body temperature methods, at ovulation time, the temperature increases $0.2^{\circ}C-0.5^{\circ}C$. Through the review of literature a high temperature above $0.2^{\circ}C$ for 3 days indicates that the previous 6 day period was ovulation and fertilization. The Symptothermal method is used to determine the prediction of ovulation through the observation of mucus excretion, high temperature, the change of cervical mucus, low abdominal pain, vaginal discharge, and breast change. Home based ovulation test kits are cervico-vaginal fluid aspiration, test a digital electric thermometer, body fluid(blood, saliva, urine) test kits, They are on the market. However, research on the contraception method is still in progress. For pregnancy it is still too early to use home based ovulation test kits because of deficit of reliability and simplicity more research on the technology is needed. It is suggested that NFP methods be included in nursing curriculum in order to educate NFP users how to effectively use NFP methods. Furthermore, this study has implications for the dissemination of NFP methods in terms of Korean policies of family planning and the support of community welfare agences.