• Journal of Educational Research in Mathematics
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• v.26 no.3
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• pp.355-370
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• 2016

This research intends to and understand a prospective teacher, Kim's mathematics lesson in the perspective of Activity Theory. In this study, Kim's mathematics lesson was explored in the aspects of subject, object, tools, division of labor, community, and rule which are main constituent of Activity Theory and Activity System suggested by $Engestr{\ddot{o}}m$. As the result of study, we discussed the phenomena such as the fluctuation between object and tool, the multi-voicedness between object, rule, outcome and student subject, and the dissonance between division of labor, community and rule were appeared in Kim's mathematics lesson as an activity system.

• Korean Journal of Legislative Studies
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• v.23 no.2
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• pp.179-217
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• 2017

The purpose of this study is to analyze the integration and separation phenomenon of the legislative network by analyzing the Legislative cosponsorship networks in the process of multicultural, family, and gender legislation. First, I analyzed the Legislative cosponsorship networks centered on the proposed bills in the Women and Family Committee. Second, Analyze the network of joint initiatives for multicultural, family, gender related legislation and representative laws in each field. In this process, we analyze who participates in the Legislative cosponsorship networks and who is the leader of the political coalition. Finally, Understand the shared characteristics and differentiated characteristics of policy networks according to policy issues.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.4
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• pp.400-406
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• 2017

The model used in this study was reversed to analyze the cause of excessive damage that occurred inside the rotating system and pipe system of a centrifugal-type seawater pump on a ship. For this purpose, internal flow analysis on a cooling seawater pump was performed using CFD. As a result, the shape and boundary conditions of the target pump were set by reverse engineering, and pump efficiency at a design operating point of $125m^3/h$ was calculated as 85.3 % with a head of 32.0 m. The maximum efficiency point of the target pump was estimated to be 86.2 % at $150m^3/h$, but this differed from the actual operating point. At $112.5m^3/h$, which was the lowest flow point, flow was unstable due to the characteristics of the low flow point and analysis convergence was not good. The purpose of this study was to clarify the cause of ongoing cavitation in seawater pumps and piping systems in operation. Future research will be needed to clarify causes for pipe systems in the future by performing calculations for the total piping system of an inlet and outlet, in addition to measuring the flow rate of each branch pipe.

• Korean Journal of Social Welfare
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• v.57 no.1
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• pp.147-167
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• 2005

In the West, the model for provision of services to the disabled has shifted from a focus on the individual to that of a social model. This shift reflects a movement away from a materialist approach to one that is grounded in idealism. In the context of themultiple service paradigm movement this paper explores trends in the provision of social services to the disabled in Korea. In order to accomplish this task the writer conducted an analysis of Korean Community Chest proposals, existing legislation and legislative systems as well as the disability movement in Korea. Data was collected from the 2003 program proposals submitted to the Korea Community Chest. This data was classified using Priestly's Multiple Service Paradigm of Disability. The results suggest that the Korean Community Chest favored an individual idealist approach. There was only limited support given to proposals that reflect the social model approach and thus issues of accessibility, independent living and inclusion are given short shrift. This paper argues the need for a reversal of this trend through the Korean Community Chest supporting issues mentioned above and that the social model should be given greater attention by this funding body. Implications for practice using the multiple paradigm model are discussed.

• Journal of computational fluids engineering
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• v.16 no.3
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• pp.37-46
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• 2011

Unsteady sheet cavitation on a three-dimensional twisted hydrofoil was studied using an unsteady Reynolds-averaged Navier-Stokes equations solver based on a cell-centered finite volume method. As a verification test of the computational method, non-cavitating and cavitating flows over a modified NACA66 foil section were simulated and validated against existing experimental data. The numerical uncertainties of forces and pressure were evaluated for three levels of mesh resolution. The computed pressure on the foil and the cavity shedding behavior were validated by comparing with existing experimental data. The cavity shedding dynamics by re-entrant jets from the end and sides of the cavity were investigated.

• Journal of Korean Library and Information Science Society
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• v.50 no.2
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• pp.191-214
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• 2019

In order to understand the trends of collaborative research in the field of Library and Information Science (LIS) in Korea, this study analyzed bibliometric data and keywords of 5,383 Journal papers by 195 Korean LIS professors from 2000 to 2017 as well as the author credit allocation formulas of 26 Korean university research evaluation criteria. Examination of university research evaluation criteria revealed co-authors' credit level to be generally much lower than that of single authors, which in turn reduces the relative value of collaborative research. As a result, recent journals publish more co-authored papers than single author papers both domestically and internationally. The study also found collaborative research to be less prevalent in private universities than national universities and least prevalent in associate professors among professors. Furthermore, keyword analysis of study data revealed the emerging topics of both domestic and international collaborative research to be those that reflect social phenomena as well as those that relate to information science employing new technologies.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.1
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• pp.61-69
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• 2004

This paper describes numerical efforts to characterize the flame-holding and air-fuel mixing process of model SCRamjet engine combustor, where a hydrogen jet injected into a supersonic cross flow and in a cavity Combustion phenomena in a model SCRamjet engine, which has been experimentally studied at University of Queensland and Australian National University using a free-piston shock tunnel, was observed around separation region of upstream of the normal injector and inside of cavity. The results show that the separation region and cavity generates several recirculation zones, which increase the fuel-air mixing. Self ignition occurs in the separation-freestream and cavity-freestream interface.

• The Journal of Engineering Geology
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• v.9 no.1
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• pp.17-29
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• 1999

There are three major processes to impact the groundwater flow near underground storage caverns in the coastal area; effect of topography, effect of sea water intrusion, and effect of excavation. In this paper, the effects of three items were numerically studied to identify the major cause for altering the flow pattern. It turned out that the excavation is the most significant effect on the groundwater flow system. The groundwater pressure distributions and consequent groundwater pathways were significantly altered near the openings. By increasing the groundwater pressures from water curtain holes, the potential leakage of storage cavern was properly prevented

• Journal of the Korean Society of Hazard Mitigation
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• v.4 no.3 s.14
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• pp.89-94
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• 2004

Recently, the cityward tendency of the population has caused the construction of a high rise apartment increased, because it is possible for many people to dwell on a small ground area in an apartment. In the future the number of the constructed high-rise apartment units will also increase, because many people require a better environment and more improved space of their life. However, apartment buildings with many dwellers in spite of small area are exposed to great dangers, particularly fire. So the adaptable control methods of smoke which is the most dangerous to people in a fire were proposed by an analysis on some standards for the fire in this study.

• Journal of the Society of Naval Architects of Korea
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• v.58 no.4
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• pp.214-224
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• 2021

Recently, as the technology of the supercavitating underwater vehicle is improved, the necessity of research for maneuvering characteristics of the supercavitating underwater vehicle has emerged. In this study, as a preliminary step to analyzing the maneuverability of a supercavitating underwater vehicle, the characteristics of cavity shapes and hydrodynamic forces generated in a supercavitating underwater vehicle with an angle of attack were evaluated numerically. First, the geometry was designed by modifying the shape of the existing supercavitating underwater vehicle. The continuity and the Navier-stokes equations are numerically solved, and turbulent eddy viscosity is solved by the k-ω SST model. The results present the characteristics of cavity shape and the hydrodynamic forces of the designed geometry with an angle of attack.