• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.484-488
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• 2010

In this study, combustion experiments of the End-Burning Hybrid Propulsion System using $GN_2O$(Gas Nitrous oxide)/HDPE were performed and the results were compared to those of the combustion experiments using GOX/HDPE. The regression rate of the solid fuel using $GN_2O$ is lower than that of the solid fuel using GOX since oxidizer inlet velocity of $GN_2O$ is lower than that of GOX. However, in case of using $GN_2O$, the characteristic velocity is higher than those of the GOX. The combustion chamber pressure and thrust were relatively kept constant during combustion.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.5
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• pp.51-59
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• 2007

The end-burning combustion field using impinging oxidizer injectors are analyzed with tangential type injectors in order to examine their mixing and combustion characteristics. The impinging type showed further improved mixing effect as well as the combustion efficiency compared to the previously studied tangential injector. A novel injector capable of delivering impinging and swirl effect is introduced in this study where it demonstrated that the grain coning effect can be avoided. It was found that the combined impinging and swirling flow would promote the radial mixing rate increasing the residence time and the turbulent intensity. However, the use of the step combustor which may augment the turbulent intensity did not show any notable difference compared to the basic combustor.

• Journal of the Korean Society of Propulsion Engineers
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• v.9 no.2
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• pp.78-88
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• 2005

The combustion characteristics of End-Burning hybrid combustor using different types of injector system are numerically investigated to visualize the temperature fields in the combustion chamber The basic characteristics of combustion with different O/F ratio is also analyzed in order to capture the main behavior of diffusion flame inside the swirl induced hybrid combustion chamber It was found that the arrangement of oxidizer injectors give strong effect on the temperature field dominating mixing between fuel and oxidizer. The results show that among five different oxidizer injectors arrangement, the counter flow injector has the highest mixing efficiency. However, the observed high wall temperature presence near the oxidizer injectors remains to be solved.

• Korean Journal of Childcare and Education
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• v.10 no.6
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• pp.291-311
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• 2014

This research is to understand young children ontologically by examining features of young children in the picture books for the early childhood. For the purpose, under the consultation with a picture book specialist and three level process of selection, 4 picture books were chosen as analytic objects. The study questions is as follows. What is ontological understandings on young children throughout picture books for the early childhood? Under this purpose the books chosen were John Burningham's , David Wiesner's , Hina Back's , Peter Sis's . The books went through dramaturgical coding and were thematised based on the theories of ontological phenomenology. Study results show that young child-being appearing in the picture-books are thematised as 'multi layered being with Ntwurf and Geworfenheit(Aldo)', 'responsible being risen above greed(Plotsam)', 'reflective being on face of others(Fairy of Jangsutang)', 'being who encourages educational response of adults.(Madlenka's Dog)' These results revealed that young child-being have features not different from (multi layered aspect of being), unique from(encouraging educational response), and beyond adult-being(responsibility and response towards others). Despite several limitations, this study helped understand the young children ontologically by revealing that they, not only as developmental beings with imperfection, dependence, and immaturity but as multi layered and requesting, responsible being, having the same features as adults and, at times, rise above adult-being.