• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.121-127
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• 2003

Wave overtopping is one of the most important hydraulic responses of breakwater because it significantly affects its functional efficiency, the safety of transit and mooring on the rear side, wave transmission in the sheltered area, rear side armor stones and to some extent, the structural safety itself. In this study, hydraulic model tests has been carried out to investigate the influence of berm's size on overtopping rate by maximum overtopping rate and mean overtopping rate. The hydrodynamic characteristics of berm breakwater by the overtopping rate can be summarized as follows: 1. It is better to use maximum overtopping rate than to use mean overtopping rate for design of coastal structures in the point of view of stability. 2. When construct berm to decrease energy of waves that it was needed to make breaking conditions of wave on the berm. 3. Under the relative length of berm was over 0.13 overtopping rate was significantly decreased. 4. Overtopping rate affected significantly by the relative length of yhe berm than height of the berm.

• Environmental Analysis Health and Toxicology
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• v.27
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• pp.3.1-3.4
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• 2012

Objectives: The current use of humidifier detergent and its harmful impact on humans has arisen as a societal environmental health issue. Therefore, in this study we aimed to explore the relationship between demo-socio characteristics and humidifier use, as well as the monthly usage changes in pregnant women; thus, we report the actual status of humidifier usage of Korea's pregnant population. Methods: From a birth cohort of a Mothers and Children's Environmental Health (MOCEH) study, 1,144 pregnant women who responded through questionnaires including demo-socio characteristics, obstetric status and household environment including whether they use humidifier and frequency of use were included in this study. Statistical analyses were performed to explore the relationship between maternal characteristics and the relevance of the use of humidifiers was performed using a chi-square test, a t-test and univariate logistic regression analysis. The monthly usage rate was demonstrated in the graph. Results: The humidifier usage rate in pregnant women was 28.2%. The average frequency of humidifier usage was 4.6 days per week, 7.3 hours per day. The usage rate was higher in the multipara group and the above the age of 34 age group than in the primipara and below the age of 34 groups. Seoul showed a higher usage rate than Cheonan and Ulsan and as the education level and income increased, the usage rate of humidifiers among pregnant women also increased. In the monthly trend of usage rate, the winter season showed the highest usage rate of over 45% and the lowest in late summer and beginning of fall with a value of 12% or less. Conclusions: During pregnancy, the mother's body is especially vulnerable to hazardous environmental exposure that not only affects the pregnant woman but also the fetus. Further research is still needed to elucidate the route and effect of environmental risk factors. Therefore, based on precautionary and preventive principles, special interest and caution in harmful environments are strongly needed not only at an individual level but also at a national level.

• Journal of Korean Academy of Nursing
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• v.4 no.1
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• pp.121-134
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• 1974

This study is an attempt to evaluate the use of an oral contraceptive by: 1. Deforming the acceptance rate of the oral contraceptive according to socio-demographic characteristics 5. Estimating the duration of the use of the contraceptive f. Discovering reasons why the contraceptive was discontinued 4. Computing the cumulative continuation and discontinuation rate according to socio-demographic characteristics, history of pregnancies, and attitude of husband at the time of selection of the contraceptive. One hundred sixty-eight women of child bearing age (14-49 years), residing in Yonhee Dong, Seoul, Korea and registered as oral contraceptive accepters at Yonsei Community Health Center, were interviewed during a three week period in 1973. The questionnaire was designed to determine the socio-demographic characteristics of the oral contraceptive accepters, the current status of their family planning practice, medical reactions if any, discontinuation practice, and the duration of the use of the contraceptive. The major findings of the study were as follows; 1. The acceptance rate was highest for women between 30 and 34 years of age, the mean age being 34.4 years. 2. Fifty six point five percent of all respondents said that thirty years of age was the ideal age to stop having children. 3. The average number of living children was 3.5 and fifty four point eight percent of respondents felt 2 boys and I girl was the ideal number of children. 4. The average number of pregnancies was 5.2 and the average number of induced abortion was I. 4. 5. Fifty eight point eight percent of the respondents had experience in the use of contraceptive methods in the past. 6. Forty one point seven percent of the respondents replied that they chose the oral contraceptive because, "it was not complicated to use." 7. Sixty four point eight percent of the women said their husband approved of their taking the pill. 8. The cumulative discontinuation rate was sixty point five percent of the total respondents for one year in first segment. 9. Sixty six point nine percent of the respondents had experienced side-effect while using the pill. The side effects for 68.9 percent of these women were castro-intestinal upsets. Twenty point eight percent of the women who had side effects consulted with medical personnel about them. Women who had more education had more side effects. 10. Seventy three point two percent of the women who discontinued the pill did so because of medical reasons. Women who were younger discontinued the pill for personal reasons more-often than older women. Among personal reasons listed for discontinuing the pill was the attitude of the husband. 11. The average duration of continuance of the contraceptive was 5.3 cycles under 29 years of age; 7.4 cycles between 30 and 34 years of age; and 8.4 cycles over 40 years of age. 12. The discontinuation rate was seem to increase sharply in the early cycle and increase more slowly in later cycle. Conclusions and suggestions: Since the attitude of the husband was shown to be important, the current family planning program should be expended to include approach to husband. For women who must use the oral contraceptive, education and support must be enhanced so that the discontinuation rate due to side effects will be decreased.

• Microbiology and Biotechnology Letters
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• v.28 no.5
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• pp.298-302
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• 2000

Fermentation parameters were estimated by use of a vent gas analyzer coupled to a computer data acquisition system in cultivation of Phellinus linteus WI-001, pro-ducer of polysaccharides known to have potent anticancer activities. Oxygen uptake rate(OUR), a critical indicator of the cells activities, was calculated by applying oxygen mass balance. In addition, by dividing the oxygen uptake rate hy the total oxygen consumed, on-line estimation of the cells specific growth rate was successfully done. It was also possible to estimate cell concentration directly bt use of oxygen-cell yield($Y_{x/o}$ ) which was obtained based on a correlation between cell growth and total oxygen consumed.

• Journal of the Korea Institute of Building Construction
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• v.7 no.2 s.24
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• pp.93-98
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• 2007

Waste of Plastic that is waste tile and waste interlocking block result, waste tile and waste interlocking block that execute an experiment to foretell practical use possibility availability as recycled aggregate for concrete giving change in the principal parts rate for coarse aggregate recycled aggregate appeared in the world by available thing to coarse aggregate to rate 10% but necessity that present amount used establishing material application standard that is crushed than uniform application standard to receive entropy of re-fresh concrete quality is judged to be.

• Journal of Environmental Science International
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• v.31 no.8
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• pp.707-713
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• 2022

This study aimed to comprehensively analyze the usage characteristics of children's parks according to location in Gangneung-si. Weekday and weekend, gender, time of stay, and usage behavior according to age group were analyzed and a video analysis of unmanned camera data for park management was conducted. On the average, the use of children's parks during spring and autumn was more than twice that during summer, and the use rate of children's parks located in old central districts by elderly people was relatively higher than the use rate of those located in housing development district. Overall, the usage ratio (24.6%) by elderly people was high, and their usage ratio (31.3%) in the morning period from dawn was significantly high. Among the usage behaviors, the rate at which dogs walk was analyzed to be somewhat high. As the usage ratio by elderly people is high with diverse usage behavior, it is necessary to provide complex functions to children's parks in the future.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.10
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• pp.78-87
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• 1996

In this paper, a remeshing criterion has been suggested in order to order to automate the remeshing decision during finite element analysis of metal forming. In order to use for the remeshing decision, two of remeshing criteria have been investigated. One is the use of error estimates based on errors in stresses and strain rate of the finite element solution and the other is the use of geometric characterisreics of distorted elements. As a result, the strain rate error estimate in power norm based on the former is found to give more valuable information about remeshing decision than the ones based on the latter. Examples are given to demon- strate the usefulness of the suggested eroor estimate as a remeshing criterion.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.574-587
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• 2017

Excessive application of nitrogen (N) fertilizer to support switchgrass growth for bioenergy production may cause adverse environmental effects. The objective of this study was to determine optimum N application rate to increase biomass yield of switchgrass and to reduce adverse environmental effects related to N. Switchgrass was planted in May 2008 and biomass yield, N uses of switchgrass, nitrate ($NO_3$) leaching, and nitrous oxide ($N_2O$) emission were evaluated from 2010 through 2011. Total N removal significantly increased with N rate despite the fact that yield did not increased with above $56kg\;N\;ha^{-1}$ of N rate. Apparent nitrogen recoveries were 4.81 and 5.48% at 56 and $112kg\;N\;ha^{-1}$ of N rate, respectively. Nitrogen use efficiency decreased into half with increasing N rate from 56 to $112kg\;N\;ha^{-1}$. Nitrate leaching and $N_2O$ emission were related to N use of switchgrass. There was no significant difference of cumulative $NO_3$ leaching between 0 and $56kg\;N\;ha^{-1}$ but, it significantly increased at $112kg\;N\;ha^{-1}$. There was no significant difference of cumulative $N_2O$ emission among N rates in crest, but it significantly increased at $112kg\;N\;ha^{-1}$ in toe. Excessive N application rate (above $56kg\;N\;ha^{-1}$) beyond plant requirement could accelerate $NO_3$ leaching and $N_2O$ emission in switchgrass field. Overall, $56kg\;N\;ha^{-1}$ might be optimum N application rate in reducing economic waste on N fertilizer and adverse environmental impacts.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3D
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• pp.383-390
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• 2008

Construction safety control system had improved constantly but the severity rate of injury don't reduced, safety level of construction don't progressed as usual. In order to reduce of the severity rate of injury safety control in site is important but it needs to improve form of system that introduce obligation of safety design and design safety appraisement, an effect use method of safety control cost. The safety control cost is problem that reduce than design cost accordance bidding rate and use a little safety facility cost compare with labor cost. This study tried reduce the severity rate of injury by propose effective improvement scheme through relevant problem analysis to the safety control cost and remove caution that the severity rate of injury don't reduced.

• Clinical and Experimental Pediatrics
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• v.61 no.8
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• pp.253-257
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• 2018

Purpose: Child safety seats (CSS) are critical for the protection of children, in case of motor vehicle accidents. Although the national legislation mandates that all newborns must be placed in an appropriately installed CSS during transportation, people often do not perceive the importance of CSS and do not use it as recommended. The purpose of this survey was to understand the use of CSS for the safe transport of newborns from hospital to home. Methods: We interviewed parents of newborn infants, using a structured questionnaire, at the time of their discharge from Cheil General Hospital & Women's Health Care Center, between May 2014 and July 2014. Results: A total of 403 participants were interviewed. The rate of CSS use was only 14.9%. Overall, 76.4% of the families interviewed were not aware about the recommendations on CSS use for newborns when travelling in a car. The provision of education on using CSS significantly influenced their rate of use. Parents who were educated about mounting the CSS in a car used it more as compared with others (25.7% vs. 12.2%) (P=0.002). Furthermore, if parents had heard about the importance or necessity of CSS, they used it more than others did (19.5% vs. 10.6%, P=0.032). Conclusion: Despite the legal regulation, most parents transport their newborn infants without a CSS while traveling from hospital to their home. The rate of CSS use was influenced by parental education and their knowledge about its necessity. Education programs for parents must be reinforced to increase the CSS use.