• Journal of radiological science and technology
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• v.1 no.1
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• pp.31-35
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• 1978

X-rays contribute to electron emission from material surfaces primarily through photoelectric interaction. A simple model is described for predicting the yield and energy spectrum of photon and Auger electrons emitted from materials exposed to X-ray with low energy. In this paper, We have calculated the yield of primary, Auger, and secondary, electrons. The results of the photoelectric yield model developed here suggests that. I) The angular distribution of emitted electrons(Per unit angle) is proportional to $sin{\theta}\;cos{\theta}$ for all electron energies and all components(Primary, Auger, or Secondary) II) The shape of the energy spectrum of the photoelectric yield is independent of angle. III) For this targets the forward and backward photoelectric yields are indentical.

• Journal of Sasang Constitutional Medicine
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• v.30 no.1
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• pp.7-13
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• 2018

Objectives On the point of modern preventive medicine, Sasang Constitutional Meidicine(SCM) has the thoughts of preventive medicine. Modern preventive medicine has the three dimensional prevention; primary, secondary and tertiary prevention. The preventive thoughts of SCM concerning three dimensional prevention have been investigated in this article. Method Materials and references were collected about the prevention of SCM. Lee Jema's books such as Donguisusebowon, Gyeokchigo and Donguisusebowon Chobonguen were included. Result and Conclusions As the primary prevention of SCM, Regimen according to ages, explanation according to health index as Myeongmaeksilsu(命脈實數), moderation of four ruinous causes such as intoxication, seduction, opulence and authority, adequate social life and control of 4 kinds of emotions(sorrow, anger, joy and pleasure) are included. As the secondary prevention of SCM, explanation according to disease index, fragile Organs and frequently acquired diseases according to constitutions are included. As the tertiary prevention of SCM, rehabilitation for the stroke patients according to constitutions is included. In conclusion, SCM has all of 3 dimensional prevention methods although that might be applied with modern considerate modification.

• English Language & Literature Teaching
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• v.15 no.3
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• pp.353-380
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• 2009

The purpose of this study is to analyze the preconceptions Korean EFL learners have about team teaching in the field of English education at a secondary level. Team teaching is a method of teaching where a Korean English teacher works in co-junction with a native English speaker. Generally speaking, when we discuss teaching methods for a foreign language, the most important objective is to improve our communication skills. The purpose of this study is to examine the effect on communication skills when team teaching is employed, and to find ways to maximize the benefit when team teaching. The underlying issues are; firstly, what are the precedent conditions for team teaching? Secondly, what are the best teaching methods and preparations for teaching materials for improving the effectiveness of team teaching? Third, how do the programs for team teaching with native teachers assist in improving the student's communication skills? Ideally, this study will assist in overcoming the fear that foreign language learners have when communicating with real native speakers.

• Journal of The Korean Association For Science Education
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• v.14 no.3
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• pp.356-365
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• 1994

A survey has been conducted on the employment test for the secondary school science teachers. The questionnaires were answered by 118 applicants who took the employment test of 1992. The adequacy of the employment test was analyzed in such categories as the evaluation weight of subjects, the length of time for the test, the number of questions, the contents and level of questions, the materials used for preparing for the test, etc. Based upon the results, several problems were pointed out and suggestions were made for the improvement of the test.

• Transactions on Electrical and Electronic Materials
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• v.8 no.5
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• pp.222-225
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• 2007

In this paper, we compared the current limiting characteristics of both the hybrid type and the flux-lock type superconducting fault current limiters(SFCLs), which have a magnetic coupling structure between a primary winding and several secondary windings. The limiting impedances of two SFCLs were derived from each equivalent circuit considering the design parameters of SFCL such as the self-inductance of secondary winding and the resistance of $high-T_C$ superconducting(HTSC) element. Through the comparison for the limiting impedances of two SFCLs considering the dependence of the HTSC element's resistance on the applying voltage into the SFCL, the hybrid type SFCL was confirmed to have larger limiting impedance with smaller resistance of HTSC element than the flux-lock type SFCL. It was expected from the analysis that the hybrid type SFCL was more advantageous than the flux-lock type SFCL from the viewpoint of the fault current limiting level.

• 연구논문집
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• s.25
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• pp.55-65
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• 1995

Three-dimensional incompressible turbulent flow fields within the passage of the steam turbine nozzle with/without tip clearance have been simulated by solving the Navier-Stokes equations with SIMPLE scheme. The extended k-e model is applied to modeling the Reynolds stresses. Grids in the computational domain are generated by solving the Poisson's equations to improve the smoothness and orthogonality. Flow losses, secondary flow, velocity profiles, and deviation angles are obtained. The computated results without tip clearance show good agreement with the experimental data.

• Transactions on Electrical and Electronic Materials
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• v.7 no.2
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• pp.87-89
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• 2006

We investigated the current limiting characteristics of flux-lock type superconducting fault current limiter(SFCL) according to inductance variation of coil 2. The flux-lock type SFCL consists of two coils. The primary coil is wound in parallel to the secondary coil through an iron core, and the secondary coil is connected to the superconducting element in series. The operation of the flux-lock type SFCL can be divided into the subtractive and the additive polarity winding operations according to the winding directions between the coil 1 and coil 2. The current limiting characteristics in two winding directions were dependent of on the ratio of the number of turns of coil I and coil 2. The fault current increased when the number of turns of coil 2 increased in the subtractive polarity winding. On the contrary, the fault current decreased under the same conditions in case of the additive polarity winding.

• Current Photovoltaic Research
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• v.4 no.4
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• pp.155-158
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• 2016

Long-term stability of dye-sensitized solar cell (DSSC) module is critical for the commercialization. We investigated the effect of sealing technology on the long-term stability of the $10cm{\times}11cm$ sized DSSC modules. We applied the concept of secondary sealing to the module and then performed several stability tests such as humidity cycle, 1 sun light soaking and outdoor stability tests. The enhanced stability was confirmed for the DSSC module employing optimized sealing materials and architectures.

• Journal of the Korean Electrochemical Society
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• v.11 no.1
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• pp.37-41
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• 2008

The effects of carbon-coated silicon anode on the electrochemical properties and structural change were investigated. The carbon-coated silicon powders have been prepared by thermal decomposition under argon/10wt% propylene mixed gas flow at $700^{\circ}C$. The surface and crystal structure of the synthesized materials were examined by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. Lithium cells with electrodes made from the uncoated and the carbon coated silicon anode were assembled and tested. The carbon-coated silicon particles merged together well after the insertion/extraction of lithium ions, and showed a relatively low irreversible capacity compared with the uncoated silicon particle.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.130-135
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• 2011

A study of the bending-extension-transverse shear coupled random response of the composite beams with thin-walled open sections subjected to various types of concentrated and distributed random excitations is dealt with in this paper. First of all, equations of motion of thin-walled composite H-type cross-section beams incorporating a number of nonclassical effects of transverse shear and primary and secondary warping, and anisotropy of constituent materials are derived. On the basis of derived equations of motion, analytical expressions for the displacement response of the composite beams are derived by using normal mode method combined with frequency response function method.