• Journal of Korea Water Resources Association
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• v.49 no.12
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• pp.995-1006
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• 2016

According to 5th IPCC Climate Change Report, there is a very high likelihood that the frequency and intensity of extreme rainfall events will increase. In reality, flood damage has increased, and it is necessary to estimate the future probabilistic design rainfall amount that climate change is reflected. In this study, the future probabilistic design precipitation amount is estimated by analyzing trends of future annual maximum daily rainfall derived by RCP 8.5 scenarios and using the scale-invariance technique. In the first step, after reviewing the time-scale characteristics of annual maximum rainfall amounts for each duration observed from 60 sites operating in Korea Meterological Administration, the feasibility of the scale-invariance technique are examined using annual daily maximum rainfall time series simulated under the present climate condition. Then future probabilistic design rainfall amounts for several durations reflecting the effects of climate change are estimated by applying future annual maximum daily rainfall time series in the IDF curve equation derived by scale-invariance properties. It is shown that the increasing trend on the probabilistic design rainfall amount has resulted on most sites, but the decreasing trend in some regions has been projected.

• Journal of applied mathematics & informatics
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• v.2 no.1
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• pp.11-16
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• 1995

Scale Invariant Transforms are defined for both one- and two- dimensioned input functions. These have the desirable properties of linearity and invariance to scale change of the input.

• Journal of Korean Neurosurgical Society
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• v.40 no.2
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• pp.84-89
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• 2006

Objective : The purpose of this study is to compare the outcomes of two methods for stabilization and fusion : Postero-Lateral Fusion [PLF, pedicle screw fixation with bone graft] and Posterior Lumbar Interbody Fusion [PLIF, cage insertion] for spinal stenosis and recurred disc herniation except degenerative spondylolisthesis. Methods : Seventy one patients who underwent PLF [n=36] or PLIF [n=35] between 1997 and 2001 were evaluated prospectively. These two groups were compared for the change of interbody space, the range of segmental angle, the angle of lumbar motion, and clinical outcomes by Prolo scale. Results : The mean follow-up period was 32.6 months. The PLIF group showed statistically significant increase of the interbody space after surgery. However, the difference in the change of interbody space between two groups was insignificant [P value=0.05]. The range of segmental angle was better in the PLIF group, but the difference in the change of segmental angle was not statistically significant [P value=0.0l7]. Angle of lumbar motion was similar in the two groups. Changes of Prolo economic scale were not statistically significant [P value=0.193]. The PLIF group showed statistically significant improvement in Prolo functional scale [P value=0.003]. In Prolo economic and functional scale, there were statistically significant relationships between follow-up duration [P value<0.001]. change of interbody space [P value<0.001], and range of segmental angle [P value<0.001]. Conclusion : Results of this study indicate that PLIF is superior to PLF in interbody space augmentation and clinical outcomes by Prolo functional scale. Analysis of clinical outcomes showed significant relationships among various factors [fusion type, follow-up duration, change of interbody space, and range of segmental angle]. Therefore, the authors recommend instrumented PLIF to offer better clinical outcomes in patients who needed instrumented lumbar fusion for spinal stenosis and recurred disc herniation.

• Atmosphere
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• v.32 no.1
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• pp.1-15
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• 2022

Recently, Japan's Meteorological Research Institute presented the d4PDF database (Database for Policy Decision-Making for Future Climate Change, d4PDF) through large-scale climate ensemble simulations to overcome uncertainty arising from variability when the general circulation model represents extreme-scale precipitation. In this study, the change of precipitation characteristics between the historical and future climate conditions in the Yongdam-dam basin was analyzed using the d4PDF data. The result shows that annual mean precipitation and seasonal mean precipitation increased by more than 10% in future climate conditions. This study also performed an analysis on the change of the return period rainfall. The annual maximum daily rainfall was extracted for each climatic condition, and the rainfall with each return period was estimated. In this process, we represent the extreme-scale rainfall corresponding to a very long return period without any statistical model and method as the d4PDF provides rainfall data during 3,000 years for historical climate conditions and during 5,400 years for future climate conditions. The rainfall with a 50-year return period under future climate conditions exceeded the rainfall with a 100-year return period under historical climate conditions. Consequently, in future climate conditions, the magnitude of rainfall increased at the same return period and, the return period decreased at the same magnitude of rainfall. In this study, by using the d4PDF data, it was possible to analyze the change in extreme magnitude of rainfall.

• Ocean Systems Engineering
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• v.12 no.2
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• pp.143-157
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• 2022

In this study, the nominal wake field of a semi-displacement type high-speed vessel was computed at full scale by using CFD (Computational Fluid Dynamics) and GEOSIM-based approaches. A scale effect investigation on nominal wake field of benchmark Athena vessel was performed with two models which have different model lengths. The members of the model family have the same Fr number but different Re numbers. The spatial components of nominal wake field have been analyzed by considering the axial, radial and tangential velocities for models at different scales. A linear feature has been found for radial and tangential components while a nonlinear change has been obtained for axial velocity. Taylor wake fraction formulation was also computed by using the axial wake velocities and an extrapolation technique was carried out to get the nonlinear fit of nominal wake fraction. This provides not only to observe the change of nominal wake fraction versus scale ratios but also to estimate accurately the wake fraction at full-scale. Extrapolated full-scale nominal wake fractions by GEOSIM-based approach were compared with the full-scale CFD result, and a very good agreement was achieved. It can be noted that the GEOSIM-based extrapolation method can be applied for estimation of the nominal wake fraction of semi-displacement type high-speed vessels.

• Proceedings of the KSRS Conference
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• v.1
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• pp.21-24
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• 2006

Processes controlling the interannual variation of mixed layer temperature (MLT) averaged over the NINO3 domain ($150-90^{\circ}W$, $5^{\circ}N-5^{\circ}S$) are studied using an ocean data assimilation product that covers the period of 1993 to 2003. Advective tendencies are estimated here as the temperature fluxes through the domain's boundaries, with the boundary temperature referenced to the domain-averaged temperature to remove the dependence on temperature scale. The overall balance is such that surface heat flux opposes the MLT change but horizontal advection and subsurface processes assist the change. The zonal advective tendency is caused primarily by large-scale advection of warm-pool water through the western boundary of the domain. The meridional advective tendency is contributed mostly by Ekman current advecting large-scale temperature anomalies though the southern boundary of the domain. Unlike many previous studies, we explicitly evaluate the subsurface processes that consist of vertical mixing and entrainment. In particular, a rigorous method to estimate entrainment allows an exact budget closure. The vertical mixing across the mixed layer (ML) base has a contribution in phase with the MLT change. The entrainment tendency due to temporal change in ML depth is negligible comparing to other subsurface processes. The entrainment tendency by vertical advection across the ML base is dominated by large-scale changes in wind-driven upwelling and temperature of upwelling water. Tropical instability waves (TIWs) result in smaller-scale vertical advection that warms the domain during La Ni? cooling events. When the advective tendencies are evaluated by spatially averaging the conventional local advective tendencies of temperature, the apparent effects of currents with spatial scales smaller than the domain (such as TIWs) become very important as they redistribute heat within the NINO3 domain. However, such internal redistribution of heat does not represent external processes that control the domain-averaged MLT.

• Tunnel and Underground Space
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• v.23 no.5
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• pp.401-412
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• 2013

Multi-stage shear test has been performed using joint specimens of gneiss, granite and shale to investigate the influence of micro-scale asperity change on the shear strength of joint plane. For each shear test asperity degradation characteristics of joint specimens of different joint surface strength have been analyzed by utilizing the optimum asperity parameter which can reflect the sequential asperity degradation. Elevation of joint surface profile has been measured and both the changes of asperity parameters and micro-scale asperity distribution have been investigated. Two distinctive variation modes of cohesion and friction angle have been delineated and major cause of shear strength parameter change has been analyzed by considering the micro-scale asperity angle change resulting from the abrasion, fracturing and regeneration of micro-scale asperities. Effects of micro-scale asperity variation on the joint shear strength have been also investigated.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.2
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• pp.65-75
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• 2010

Space transformation of hospital architecture happens more rapidly than other types such as school and office buildings. This requirement is caused by medical demand, service transformation, technical development and equipment changes. Grand scale extension and rapid change in hospital architecture affects whole planning; therefore, it is important to design in the macro perspective such like Life Cycle. Grand scale extension is difficult process to rebuild growth and transfer of hospital architecture and to adapt to the future change. That's why simple planning gives limits to some departments in a short-term and brings another reform such as more extension or interior renovation in a long-term. This study surveys various space transformation and grand scale extension of EB hospital extended recently, and it is to find planning condition in extension.

• Human Ecology Research
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• v.52 no.4
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• pp.405-414
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• 2014

The purpose of this study was to investigate the influences of organizational culture and childcare teachers' job satisfaction on their intention to change jobs. The participants of this study were 290 childcare teachers from the Busan and Gyeongnam areas. The instruments used in this study were the Organizational Culture Scale (4 factors with 16 items), Childcare Teacher's Job Satisfaction Scale (6 factors with 40 items), and Childcare Teacher's Intention to Change Jobs Scale (1 factor with 7 items). The data were analyzed by descriptive statistics, one-way analysis of variance, Pearson's product moment correlation, and stepwise multiple regression with SPSS ver. 21.0 software. The results were as follows: First, the higher childcare teachers' intention to change jobs, the lower was their monthly income, age, and career level, and the total number of children that they had to serve. Second, there were significant positive correlations between childcare teachers' intention to change jobs and their innovative, collective, and rational organizational culture. Further, there were significant negative correlations between childcare teachers' intention to change jobs and hierarchical organizational culture. and between childcare teachers' intention to change jobs and their job satisfaction. Finally, childcare teachers' intention to change jobs was found to be 46% about job satisfaction and organizational culture and was explained the most by the director's childcare center management. This study primarily suggests that a director's role is important in the lowering of childcare teacher's intention to change jobs.

• The Research Journal of the Costume Culture
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• v.6 no.2
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• pp.92-108
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• 1998

The purpose of this study was designed a) to examine the relative importance for college students' clothing disposal causes and their factor structure: b) to test the effects of gender, clothing satisfaction and family income on clothing disposal determinants; and c) to assess the relationship between clothing purchase determinants and overall clothing satisfaction and clothing disposal determinants. Data (n=660) were collected from college students in Cheju Do. The survey questionnaire composed of a revised Clothing Disposal Determinants Scale, Clothing Purchase Determinants Scale and background variables. First, the most important reasons for clothing disposal were to unfit with body change, get washed our and raise nap on clothe, wornout with long-term use, do not ware for new purchasing clothe, uneasy on wear. Second, factor analysis of the revised Clothing Disposal Determinants Scale revealed five factors; unfitness, fashion change, quality dissatisfaction, product efficiency decrement, and maintenance/inconvenience. Third, female students perceived significantly higher in fashion change and unfitness than male students. Forth, unfitness and product efficiency decrement were significantly discriminated between between clothing satisfaction groups, unfitness and fashion change variables were significantly discriminated between family income groups. fifth, impulsive purchase factor was the best predictor of composite clothing disposal measure, followed by individuality, clothing satisfaction, practicality. The best predictors of each disposal factors were individuality oriented purchasing criterion in unfitness factor. Fashion in fashion change, impulsive purchase in quality dissatisfaction and product efficiency decrement factors, and practicality in maintenance/inconvenience factor. As a whole, the most consistent predictor of clothing disposal determinants was impulsive purchase factor.