• Journal of Korea Technology Innovation Society
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• v.17 no.2
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• pp.355-379
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• 2014

For the transition to the low carbon society, it is inevitable but difficult journey that the new energy technology spread co-exists with formal social system. The objective of offshore wind power plant that has been implemented by the government is to connect large capacity new renewable energy to the central electric power system. Therefore, for the successful introduction of offshore wind power system, the transition of the formal social technology system should be companied. This study analysis the energy system transition about niche strategy adjustment using Multiple Level Perspectives & Strategic Niche Management. It also multi level analyzes and structuralizes the process that new technology, as a research result, evolves through connecting and communicating with formal regime and landscape. Also, adjusting Strategic Niche Management, it diagnoses the obstructive factors in the initial stage of niche experiment and found the major reasons why offshore wind power test plant had been delayed. Through this study, it reaches to the practical implication that offshore niche technology could grow stably in the energy system and various policies.

• Journal of Korean Clinical Nursing Research
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• v.23 no.2
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• pp.151-160
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• 2017

Purpose: The purpose of this study was to evaluate the effects of oral stimulation interventions on the transition from tube to oral feeding in preterm infants through systematic review. Methods: The randomized clinical trials published between 1980 and 2015 were searched using domestic and international databases, and five randomized studies were selected for this study. The quality of study was assessed by assessment tool from the SIGN and meta-analysis was performed using the Cochrane Review Manager software Version 5.3 (RevMan). Results: Oral stimulation intervention in preterm infants decreased the transition time from tube to oral feeding (Post Menstrual Age, Day of life). Especially, a significant medium effect size was found in the number of days needed on the transition (ES=-4.95, p=.02). The oral stimulation intervention also had a significant large effect on the length of stay at hospital (ES=-8.33, p<.001). Conclusion: Based on the findings, oral stimulation interventions could be useful to facilitate the transition from tube to oral feeding in preterm infants in terms of reducing the length of stay at hospital and the number of days needed on transition.

• Journal of Environmental Science International
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• v.21 no.7
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• pp.787-795
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• 2012

The purpose of this study is to synthesize transition metal doped mesoporous silica catalyst and to characterize its surface in an attempt to decomposition of $N_2O$. Transition metal used to surface modification were Ru, Pd, Cu and Fe concentration was adjusted to 0.05 M. The prepared mesoporous silica catalysts were characterized by X-ray diffraction, BET surface area, BJH pore size, Scanning Electron Microscopy and X-ray fluorescence. The results of XRD for mesoporous silica catalysts showed typical the hexagonal pore system. BET results showed the mesoporous silica catalysts to have a surface area of 537~973 $m^2/g$ and pore size of 2~4 nm. The well-dispersed particle of mesoporous silica catalysts were observed by SEM, the presence and quantity of transition metal loading to mesoporous surface were detected by XRF. The $N_2O$ decomposition efficiency on mesoporous silica catalysts were as follow: Ru>Pd>Cu>Fe. The results suggest that transition metal doped mesoporous silica is effective catalyst for decomposition of $N_2O$.

• Water for future
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• v.28 no.2
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• pp.137-143
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• 1995

The location and the shape of freshwater-saltwater transition zones in coastal aquifers are affected by many hydraulic variables. To date most work to determine the effects of these variables are limited to qualitative comparison of transition zones. In this work characteristics of transition zones (maximum intrusion length, thickness, and degree of stratification) are quantified, and effects of principal hydraulic variables(velocity and dispersivity) on these characteristics are studied using a numerical model. Dimensional analysis is used to assemble entire model results. Effects of velocity and dispersivity are seen clearly. From this study, increase in velocity is found to cause shrinkage of transition zones. This observation contradicts claims by some that, because dispersion is proportional to velocity, increase in velocity would cause expansion of transition zones.

• The Transactions of the Korean Institute of Power Electronics
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• v.21 no.3
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• pp.238-248
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• 2016

In this study, an automatic command mode transition strategy of direct power control (DPC) is proposed for permanent magnet synchronous generators (PMSGs) medium-voltage (MV) offshore wind turbines (WTs). Benchmarking against the control methods are performed based on a three-level neutral-point-clamped (NPC) back-to-back type voltage source converter (VSC). The ramping rate criterion of complex power is utilized to select the switching vector in DPC for a three-level NPC converter. With a grid command and an MPPT mode transition strategy, the proposed control method automatically controls the generated output power to satisfy a grid requirement from the hierarchical wind farm controller. The automatic command mode transition strategy of DPC is confirmed through PLECS simulations based on Matlab. The simulation result of the automatic mode transition strategy shows that the proposed control method of VOC and DPC achieves a much shorter transient time of generated output power than the conventional control methods of MPPT and VOC under a step response. The proposed control method helps provide a good dynamic performance for PMSGs MV offshore WTs, thereby generating high quality output power.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.351-356
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• 2000

Various transition elements are generally used for the effective analysis of a complicated mechanical structure. In this paper, a solid-to-beam transition finite element which connects a continuum element and a $c^1-continuity$ beam element each other is proposed. The shape functions of the transition finite elements, which a 8-noded hexahedral solid element fur 3D analysis and a 4-noded quadrilateral plane element fur 2D analysis are connected to a Euler's beam element, are explicitely formulated. In order to show the effectiveness and convergence characteristics of the proposed transition elements. numerical tests are performed for various examples and their results are compared with those obtained by other methods. As the result of this study. following conclusions are obtained: (1)The proposed transition finite elements show the monotonic convergence characteristics because of having used the compatible displacement folds. (2)As being used the transition element in the finite element analysis, the finite element modelings are more convenient and the analysis results are more accurate because of the formulation characteristies of the Euler's beam element.

• Journal of Korean Academy of Nursing
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• v.34 no.2
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• pp.243-251
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• 2004

Purpose: The purpose of this study was a comprehensive understanding about maternal transition in mothers with high risk newborns according to the degree of situational meaning. Method: A methodological triangulation that combines qualitative and quantitative methods was used. The situational meaning of a high risk newborn mother was identified using a Family Meaning Attribution Scale. According to the degree of situational meaning, in-depth interviews were conducted at 3 time periods postpartum: between 3-10 days after childbirth, around the time of the newborn's discharge, and between 10-12 weeks after childbirth. Quantitative data was analyzed using descriptive statistics and t-test. Qualitative data was analyzed using Tutty, Rothery, & Grinnell's methodology. Result: The average score of the situational meaning in high the risk newborn mother was 53.57(possible score is between 0-96) and the average score of each item was 1.67. A Maternal transition process in the mother that has a positive situational meaning was conceptualized in three distinctive phases: confusion, accepting, and shaping phases. The Maternal transition process in the mother that has a negative situational meaning was also conceptualized in three distinctive phases: avoiding, conflicting, and accepting phases. Conclusion: It is necessary that the nurses provide high risk newborn mothers with individualized care considering both the situational meaning that is attributed to them and the maternal transition phase that they are faced with.

• Journal of the Korean Society for Heat Treatment
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• v.6 no.4
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• pp.204-212
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• 1993

The preparation of $TiO_2$ fine particles from $TiCl_4$ and oxygen by the vapor-phasereaction was investigated at $850^{\circ}C$ with an emphasis on the effect of its experimental conditions on the crystal type of the products. Anatase $TiO_2$ particles prepared by experiment were used to study anatase-rutile transition by calcination temperature, the additives and gas atmosphere. The results were as follows. The kinetics of anatase-rutile transition was well agreed with A vrami equation, and the activation energy of transition was 35kcal/mol. The addition of CuO in anatase $TiO_2$ particles accelerated the anatase-rutile transition, and its transition was retarded in vaccum.

• Bulletin of the Korean Chemical Society
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• v.30 no.12
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• pp.2973-2978
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• 2009

The decomposition reaction mechanism of $CH_3CF_2O$ radical formed from hydroflurocarbon, $CH_3CHF_2$ (HFC-152a) in the atmosphere has been investigated using ab-initio quantum mechanical methods. The geometries of the reactant, products and transition states involved in the decomposition pathways have been optimized and characterized at DFT-B3LYP and MP2 levels of theories using 6-311++G(d,p) basis set. Calculations have been carried out to observe the effect of basis sets on the optimized geometries of species involved. Single point energy calculations have been performed at QCISD(T) and CCSD(T) level of theories. Out of the two prominent decomposition channels considered viz., C-C bond scission and F-elimination, C-C bond scission is found to be the dominant path involving a barrier height of 12.3 kcal/mol whereas the F-elimination path involves that of a 28.0 kcal/mol. Using transition-state theory, rate constant for the most dominant decomposition pathway viz., C-C bond scission is calculated at 298 K and found to be 1.3 ${\times}$ 10$^4s{-1}$. Transition states are searched on the potential energy surfaces involving both decomposition channels and each of the transition states are characterized. The existence of transition states on the corresponding potential energy surface are ascertained by performing Intrinsic Reaction Coordinate (IRC) calculation.

• Asia-Pacific Journal of Business
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• v.10 no.1
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• pp.87-103
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• 2019

In December 2017, the Moon Jae-in administration announced a major policy shift away from nuclear and coal, committing itself to the vision of creating a society where renewable sources account for 20% of its electricity generation by 2030. This energy transition involves not just a technical transition from conventional energy sources to renewable energy but also active participation of multiple stakeholders in the energy governance. While energy policy making has long been dominated by the central government in Korea with the aim of managing the supply for rapid industrialization and economic growth, the Moon administration aims to diffuse the central government's authority across various actors in society. Among those actors, this study focuses on the roles that local governments play in energy transition. Despite deepening local autonomy since 1995, Korean local governments have remained policy targets or recipients in the energy policy domain. This article discusses how such a traditional role has evolved under the new administration's energy transition policy and examines what challenges and limitations local governments face in creating a more decentralized energy governance system.