• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.1-9
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• 2019

GGBFS(Ground Granulated Blast Furnace Slag), one of the representative concrete mineral admixtures, improves the long-term durability and engineering performance of concrete by latent hydraulic activity. In this study, considering 3 levels of W/B(0.37, 0.42, 0.47) and GGBFS replacement ratio(0 %, 30 %, 50 %), durability performances for chloride attack are evaluated, and equations which predict behavior of accelerated chloride diffusion are proposed. Also, the relationship between accelerated chloride diffusion coefficient and passed charge is evaluated. In target curing day, accelerated chloride diffusion tests(Tang's method, ASTM C 1202) and compressive strength(KS F 2405) are performed. In the 730 day's results of accelerated chloride diffusion coefficient, GGBFS concrete has up to 28 % of decreasing ratio compared to OPC concrete, and in those of passed charge, GGBFS concrete has up to 29 % of decreasing ratio compared to OPC concrete. Also, it is deemed that the impact of variation of W/B is less in GGBFS concrete than in OPC concrete. The equations which predict accelerated chloride diffusion coefficient and passed charge are drawn, based on the characteristics of mixture and test results. The equation which predicts passed charge shows slightly higher coefficient of determination than that which predicts accelerated chloride diffusion coefficient.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.60-67
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• 2013

A laboratory experiment was conducted to determine the content of phenolics and flavonoids, antioxidant activity and antioxidant enzyme activity for the extracts from cowpea seed and sprouts. Plant length and weight of cowpea sprouts were significantly increased until 7 days after seeding. Total phenolics level [mg chlorogenic acid equivalents (CAE) $kg^{-1}$ DW] was highest in dry seed (DS) extracts of cowpea ($63.9mg\;kg^{-1}$), followed by imbibed seed (IS) ($56.8mg\;kg^{-1}$) and 1-day-old sprout (1DOS) extracts ($46.4mg\;kg^{-1}$), and significantly reduced with increase of sprout age (p < 0.05). The antioxidant activity of the methanol extracts from all the samples showed same tendency to the results of total phenolics level, and dose-dependently increased. DPPH (1,1-diphenyl-2-picryl hydrazyl radical) free radical scavenging activity was higher in DS (87.3%) and IS (41.2%) than in cowpea sprouts from 1DOS to 7DOS, ranging from 17.1 to 30.4%. Antioxidant enzymes, APX, POX, and POX activities were highest in 7DOS and lowest in DS. SOD activity showed much higher activity in sprouts and in seeds. Correlation coefficient between physiological-active substance and the activity was highest between APX and CAT activities ($r^2$= 0.9574). Especially, total phenolics content was more highly correlated with antioxidant or with antioxidant enzyme activities than was total flavonoid level.

• Bioinformatics and Biosystems
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• v.1 no.2
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• pp.115-122
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• 2006

A three-dimensional pharmacophore model was developed based on 24 currently available inhibitors, which were rationally selected from 472 compounds with diverse molecular structure and bioactivity, for generating pharmacophore of uPA (Urokinase Plasminogen Activator) inhibitors. The best hypothesis (Hypo1) comprised of five features, namely, one positive ionizable group, one hydrogen-bond acceptor group and three hydrophobic aromatic groups. The correlation coefficient, root mean square deviation and cost difference were 0.973, 0.695, and 94.291 respectively, suggesting that a highly predictive pharmacophore model was successfully obtained. The application of the model showed great success in predicting the activities of 251 known uPA inhibitors (test set) with a correlation coefficient of 0.837, and there was also none of the outcome hypotheses that had similar cost difference and RMS deviation (RMSD) with that of the initial hypothesis generated by Cat-Scramble validation test with 95% confidence level. Accordingly, our model should be reliable in identifying structurally diverse compounds with desired biological activity.

• Journal of environmental and Sanitary engineering
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• v.11 no.2
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• pp.27-31
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• 1996

2,4,6-Trinitrotoluene(TNT) was reduced into intermediate products by mixed culture incubated in anaerobic condition. To test the effects of extracellular material to electron transfer between sulfide and TNT, filtered medium of mixed culture was loaded in the test tubes with TNT and sulfide. The transformation rate was measured under four different conditions. The rate under microbial activity was the fastest among under different conditions. With sulfide or filtrate alone and TNT, the reactions were measured as the slowest reactions or no reactions occured, respectively. The reaction rate coefficient were calculated by linear regression and the first order kinetic was fitted best. Also, the plot of rate coefficients (K$_{f}$) showed linear relationships when at time zero TNT and sulfide concentration were 20 mg/1 and 6.0 mM, respectively. By extrapolation, reaction rate coefficient of 100% filtrate could be calculated as 0.0054/minute. However, reaction rate was affected by different concentration of sulfide, so it is a dependent of sulfide concentration. The results of this test showed TNT reduction rate can be limited more by microbial reaction than by mediation of filtrate or sulfide and filtrate alone.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.463-469
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• 2014

Safety related devices unconstrained temporally in the process of operation of nuclear power plants could be damaged by the sliding during seismic activity. In this study sliding response of unconstrained objects to the base excitations is studied experimentally and analytically. In experiments static and dynamic tests to determine the coefficient of friction and the shaking table experiments to verify the sliding response of the analytic results were conducted. Numerical solutions by solving the nonlinear differential equations of motion governing sliding were found by the computer program using the step by step acceleration method. The exact solutions of the sliding response to the simple forms of base excitations were found to verify the computer program developed in this study. Relative displacement envelopes were suggested as a colliding criteria of the unconstrained objects.

• Women's Health Nursing
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• v.10 no.4
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• pp.342-350
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• 2004

Purpose: It has been suggested that approximately 40% of women between 40 and 64 years of age cease their sexual activity. The aim of this study was to establish the basic data for FSD(female sexual dysfunction) and FSD-related factors in regional urban and rural areas of Korea. Method: Three hundred twenty five women over 20 years of age and resident in regional urban and rural areas were analyzed by a visit survey with an organized questionnaire. The female sexual function index(FSFI) for measurement of sexual dysfunction was used. The significance between the degree of sexual dysfunction and characteristics of the participants was analyzed by a t-test and ANOVA test. The relationship between the degree of sexual dysfunction and related factors was analyzed by Pearson's correlation coefficient. Results: All analyzing tools including the FSFI had a high validity for measuring. The FSFI in Korean women was $19.97{\pm}4.87$ and ranged from 2 to 29. Old age, menopause, medication, no contraception usage and longer marital duration were significantly related with a lower FSFI score. Pearson's correlation coefficient revealed the significance in degrees of sexual distress (r=-.469, p=.000), sexual attitude(r=.305, p=.000) and a stressful life event(r= -.141, p=.038) with the sexual function index score. Conclusion: Women with sexual dysfunction should be evaluated for these sexual function-related factors in the history taking, and this data can be a basis for study for sexual dysfunction.

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.293-306
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• 2013

According to the increase of rural experience, that is important in satisfying needs of green tourism and vitalizing rural economy to use closed school in rural area as experience facility. For using closed school as experience facility, political and institutional assistants are needed in effective equipments and stable operation based on multi-perspective approach and analysis. In this study, we try to evaluate green-tourism accessibility of rural experience facility remodeled from closed school considering regional population and spatial characteristics. In evaluating process, gravity potential model are adapted with considering group size of customer and distance-friction coefficient. Distance-friction coefficient is a function of user restriction which depend on possible activity in each experience facility. Green tourism accessibility of experience facility is calculated with summation of accessibility to each region, and we analyzed it as a group by closed school type and location with application in Chungcheongnam-do. We found a correlation between green tourism accessibility of rural closed school and their income.

• Journal of the Society of Naval Architects of Korea
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• v.33 no.4
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• pp.124-132
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• 1996

This paper discusses a scheduling system effective for producing optimum load distribution in ship design process with particular reference to an accommodation design. Through various analysis of the factors influencing the effectiveness of design process control, it was possible to formulate an algorithm of producing an optimum design schedule. Basic manhours far the ship to be planned by multiplying a difficulty level coefficient for the standard manhours for each design activity is preset, and is converted into manhours for the ship to be planned by multiplying a difficulty level coefficient for the ship. A relation matrix of the design activities is employed in representing the network of the activities. The computerized system showed very effective in producing a design schedule of leveled work load on which particular characteristics of a ship to be planned are properly reflected.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.34
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• pp.155-159
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• 1995

For the relationship between conformance cost and the individual elements of non-conformance, an analysis was made of the relationship between inspection cost and training cost and scrap cost. As a result it was explained that there was all a positive correlation between training cost and scrap cost, and between inspection cost and scrap cost. Like this, training and inspection cost and scrap cost have a positive correlation. Judging from the fact that the coefficient of inspection cost is lower than that of training cost in the comparison of the coefficient of each cost, it can be analyzed that the change in scrap cost is influenced by the change in training cost more greatly than the change in inspection cost. If doing so, it can be interpreted that scrap cost and rework cost do not still decrease in spite of increasing in education and training cost and prevention cost. This result may represent the problem as to whether education and training cost is effectively expended for prevention activity. Accordingly, to cope with this situation, it is thought that scrap cost should be cut by establishing the effective prevention measure for causing the increase of scrap cost.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.2
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• pp.85-92
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• 2007

In 1980s, a number of bridges with bare concrete deck were constructed on the Korea highway. After 20 years service, many bare concrete decks are still in good condition without special maintenance activity. Therefore, the application of the bare concrete deck is being reestimated from the view of construction and maintenance. As a part of the program, the characteristic of penetration(surface chloride and apparent diffusion coefficient) of de-icing salt into bare concrete bridge deck was analyzed in order to predict the service life of bridge on Korea highway.