• Journal for History of Mathematics
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• v.27 no.3
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• pp.233-253
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• 2014

In this study, the kindergarten teachers and elementary school teachers were surveyed to see the level relevance of the kindergarten and primary school curriculums. As a result, first, the kindergarten curriculum was generally appeared appropriate to the level of kindergarten students. However, in practice, a significant amount of the first grade curriculum were taught in the kindergarten. Second, the variation of mathematical abilities among the begining students was very large, and this variation also affected the students' achievements. Third, both kindergarten teachers and elementary school teachers wished for adjustments of the level of mathematics curriculum.

• Korean Journal of Environmental Agriculture
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• v.12 no.3
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• pp.264-280
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• 1993

The environmental pollutions were a serious problem in Korea recently. So many researcher have studied the effect of environmental pollution on plants and agro-ecosystem, but the basic mechanisms of environmental stresses were various. One of the important mechanisms was oxidative stress caused by active toxic oxygen. The toxic oxygen was generated by several stresses, abnormal temperature, many xenobiotics, air pollutants, water stress, fugal toxin, etc. In the species of toxic oxygen which is primary inducer of oxidative stresses, superoxide, hydrogen peroxide, hydroxyl radical and singlet oxygen were representative species. The scavenging systems were divided into two groups. One was nonenzymatic system and the other enzymatic system. Antioxidants such as glutathione, ascorbic acid, and carotenoid, have the primary function in defense mechanisms. Enzymatic system divided into two groups; First, direct interaction with toxic oxygen(eg. superoxide dismutase). Second, participation in redox reaction to maintain the active antioxidant levels(eg. glutathione reductase, ascorbate peroxidase, etc.).

• English Language & Literature Teaching
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• v.16 no.3
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• pp.207-229
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• 2010

The present study has sought to explore the critical issues of English immersion education through the voices of the four elementary teachers who have recently taught at immersion programs under the guidance of Busan Metropolitan City Office of Education. The interview data with three teachers and the teaching journals of one teacher were analyzed and categorized into two emergent themes: (1) current difficulties in the immersion programs and (2) possible problems with the implementations of immersion programs in all public schools. Specifically, the first issue included teachers' inadequate teaching skills for immersion programs, accumulated learning losses, and lack of immersion class hours. The second issue included workload imposed on immersion program teachers, promotion of private education, learning losses of other subjects, and administration for show. Finally, pedagogical implications are suggested.

• 전기의세계
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• v.13 no.2
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• pp.1-4
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• 1964

Phase transformation is used to change some phase from phase in A.C. system. We have been used Scott or Fork connection in phase transformation the otherwise phase transformation was constructed from M-G set. From this M-G set, we could make phase shift facilities by mannual. Now, I can derive more easy phase transformation from taking another method. I believe this new phase transformation method in the first thing in the world. And so, I am going to explain about phase transformer construction process. The first, we could devide into equal part of core around the iron core as to be same size. The second, you will make primary and secondary winding on the core. The third, when you will supplied three phase A.C. at the terminal of primary winding you can get e.m.f. inducing of some phase at secondary. And so, we could make phase change from some phase A.C. We can apply this principle in many fields, i.e., freequency changer, phase leader of no use condenser, voltage regulator in keeping balance, and D.C. generator. And more, I will introduce in details concerning main pinciple and theory through following chapter.

• The Journal of Korean Medical History
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• v.29 no.1
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• pp.1-9
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• 2016

The word Euisaeng (醫生) is shorthand the Euihaksaengdo (medical cadets), that means has been changed according to the times. Throughout the Goryeo dynasty, Euisaeng was not mean medical student, but also primary healthcare. Existing research on Euisaeng of Joseon dynasty has been grouped together, despite the identity and characteristic differences between the central and local Euisaeng. The authors have separated the two, and a review of the literature focuses on local Euisaeng. The authors found the following facts in this study. First, status of Oebang-euisaeng (local medical cadets) was declined in the latter than in the early Joseon. Second, Oebang-euisaeng of the late Joseon was Layered Hyang'ri. Third, The local medical cadets was important, the role of primary healthcare. On the other hand, The central medical cadets was important, the role of a student learning medicine.

• The Korean Journal of Cytopathology
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• v.19 no.1
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• pp.16-26
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• 2008

The lungs are one of the most common visceral sites for metastatic disease. The identification of a metastasis from a second primary lung tumor is clinically important for patients with pulmonary metastases of an extrathoracic origin. Although the cytologic features of metastatic tumors involving the lung have been extensively described, making the cytologic diagnosis is usually not easy in the absence of clinical information. However, the immunohistochemical staining for many tumor markers and the different expressions of cytokeratin 7 and 20 are very useful in the diagnosis. This review presents the cytomorphological spectrum of metastatic tumors along with the immunohistochemical findings.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.10a
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• pp.282-287
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• 1996

The non-linear torsional vibrations of the propulsion shafting system with viscous damper are considered. The motion is modeled by non-linear differential equations of second order. the equivalent system is modeled by two mass softening system with Duffing's oscillator. The steady state response of a equivalent system is analyzed for primary resonance only. Harmonic balance method as a non-linear vibration analysis technique is used. Jump phenomena are explained. The primary unstable region obtained by the Mathieu equation is investigated. Both theoretical and measured results of the propulsion shafting system are compared with and evaluated. As a result of comparisons with both data, it was confirmed that Duffing's oscillator can be used as a analysis method in the modeling of the propulsion shafting system attached viscous damper with non-linear stiffness.

• Health Policy and Management
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• v.2 no.2
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• pp.90-111
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• 1992

Community involvement is to be the keystone of primary health care, Unfortunately, efforts to promote it failed in many countries. Author inquired into the reasons why such efforts fail, and the alternative strategies for effectively promoting it in Korean situation today. In doing so, the concept of community involvement is clarified as an amalgamation of two different concepts; one is that of the community development, and the other is that of approaches for overcoming the alienation of the people from the health care process. Stategies of community involvement in Korea so far followed the line of the community development, e.g. village health worker. It loses, however, the feasibility as Korea has experinced so cial and economic developpment. The strategies of the second line of thought is now more feasible; empowering the people by providing more information and enhancing comitment to health, improving acceptabilty of community involvemt on the part of the health professionals and the bureaucrats, and building the mechanism of community involvement into the health policy-making process.

• International Journal of Contents
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• v.14 no.4
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• pp.65-69
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• 2018

The objective of this study was to conduct a radiation shielding analysis for the facility equipped with radiation generator. The analysis was carried out in two aspects. First, from the aspect of the effect caused by primary and leakage radiation. Second, effect of scattered radiation was evaluated by applying a simple calculation method based on a scattering rate concept since effect of scattered radiation is significantly important at maze entrance of the radiation facility. The calculated results obtained using the simple method were compared to the results calculated using Geant4 code and the measured values. The results calculated by the suggested method indicate that slight error exists in a radiation shielding analysis done at the maze entrance comparing to other two results, while the results evaluated at the outside of the maze entrance door are relatively consistent with other values.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.4
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• pp.294-302
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• 2019

A capacitor common connected LLC resonant converter with auxiliary switches for a wide output voltage control range is presented in this paper. The proposed converter can be controlled in two ways to achieve a wide output voltage control range of Vo-3Vo. The first control method is performed through pulse width modulation of the auxiliary switches and primary switching devices. The second control method is conducted through frequency modulation of the primary switching devices configured to operate in full-bridge switching modes, when the auxiliary switches are turned off. The feasibility of the proposed converter is verified by the experimental results of a 5 kW prototype.