• 전기의세계
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• v.26 no.4
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• pp.68-72
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• 1977

The main purpose of this paper is to study on the nature of the traps in polymer. The polyethlene is typical of polymer material as to be selected for a sample. The current I$_{th}$ are obtained with an small external bias voltage from high density polyethylene which have been treated by the high-field application. Two peaks, P$_{1}$ and P$_{2}$ with maxima near 85.deg. C, respectively, appeared on the current I$_{th}$ spectrum. From the results of experiment, It is clear that The current I$_{th}$ arises from the drift, under the external field, of carriers released from the trap sites by the heating and the trap is surrounded by a potential barrier and trapping proceeds during the high-field treatment. The obtained results can suggest that polyethylene contains trap sites which have an important role in the electrical conduction and breakdown of polymeric materials.rials.

• Journal of the Korean Institute of Navigation
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• v.15 no.3
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• pp.53-72
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• 1991

The marine cargo insurance compensates the cargo losses that happened during navigation . at the early days of the marine insurance, the insurer inclusively covered all risks that happended during navigation. But since the feature of the risks have been changed due to the development of the shipbuilding technique and commerce, the insurer could not bear all of the perils inclusively. So, the insurer have taken the limitation of the risks insured and the losses paid by exclusion clauses. Therefore, the purpose ;of this paper is to compare the exclusion clauses in the new Institute Cargo Clause (hereafter I.C.C.) with those in the former I.C.C.(all risks, F.P.A) and to make clear the scope of insurer's liability through the theoretical interpretation, clarification of various excluded risks in laws and clauses relating to marine cargo insurance. From what 1 mentioned above, 1 conclude that through continued study on the exclusion sin the new I.C.C., we should organize and establish a system which will satisfy both underwriters and the assured in making the application and the effectiveness equal for each party.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.488-491
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• 2000

Bi-2223/Ag superconducting wires have been mainly prepared by a powder-in-tube method. The drawing and the rolling are main processes to increase the core density and wire length. In the fabrication of long wire, especially, the drawing should be precisely controlled to assure the filament homogeneity. In this paper, the influences of drawing die angle, bearing length and reduction ratio on the sausaging and the critical current density of the wire are investigated. Single cored and multi-filamentary wires are fabricated by PIT method with different conditions. The core densities and sausaging in the wires are investigated and are discussed regarding their relationship to the I$_{c}$. It was made clear that the geometry of drawing die is sensitively dependent on the sausaging. The improvement of I$_{c}$ was achieved by reducing the die angle and high core density.ity.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.131-141
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• 2021

Simulation is a widely used functional verification method for FBD programs of PLC-based digital I&C system in nuclear power plants. It is difficult, however, to estimate the thoroughness (i.e., effectiveness or quality) of a simulation in the absence of any clear measure for the estimation. This paper proposes two sets of structural coverage adequacy criteria for the FBD simulation, toggle coverage and modified condition/decision coverage, which can estimate the thoroughness of simulation scenarios for FBD programs, as recommended by international standards for functional safety. We developed two supporting tools to generate numerous simulation scenarios and to measure automatically the coverages of the scenarios. The results of our experiment on five FBD programs demonstrated that the measures and tools can help software engineers estimate the thoroughness and improve the simulation scenarios quantitatively.

• Atmosphere
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• v.26 no.1
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• pp.185-192
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• 2016

In this paper, I studied about historical seasonal subdivision system and a theory of traditional monthly order, which was used for so long from Koryo dynasty to the late of Choseon dynasty in Korean histoy. Especially, I took note of the fact that there used the table of solar terms and meteorological observation what we called the table of Kihoo-pyo in the historical Sunmyung-calendar and the Soosi-calendar during the Koryo dynasty. This table of Kihoo was developed for explaining meteorological change during a year at that time. Here are largely four elements related meteorological nature : the first is the list of 24 solar terms, and the second is 12 monthly seasonal terms and 12 monthly central terms, the third is about four right hexagon based I-ching, the fourth is 72 meteorological observations called 72-hoo. Among them, the 72-hoo system is important to know how premodern people observed natural materials including animals and plants, weather, climate about meteorological phenomena according to the seasonal change or solar terms' change during a year. I argued in this article to need developing modern new table of Kihoo system like that, in order to show common people to recognize annual meteorological change more easy and clear. I also argued to need a distinct definition of meteorological seasons from a view point of modern meteorology.

• Journal of the Korean earth science society
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• v.34 no.5
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• pp.428-434
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• 2013

In this commentary, I examined the implications of Existentialism for science teaching and teacher education. Existentialist thoughts and premises can be used to explore the human element in an educational system. Before emphasizing the pragmatic and technical aspects of teaching, we need to rethink why we teach and recognize our learners as unique beings in a continual process of becoming. By incorporating the existential perspective into curriculums and pedagogies of science education, we can help learners to make their existences and experiences meaningful. This paper consists of three parts. In the first part, I drew on relevant aspects of Existentialism and its implications on the views of the learner. In the second part, I examined the competency-based curriculum in light of Existentialism. Existentialism aims, in part, to develop an educated person who possesses a clear sense of personal identity, a critical attitude, and the inclination to be a life-long learner, and so on. These characteristics are consistent with the implications developed from the competency-based curriculum. In the third part, I explored pedagogical activities consistent with existentialist thinking the ultimate goal of which is to create authentic individuals who can take responsibility for being humans. In the conclusion, I discussed how existentialist ways of thinking and teaching call for the science teacher's reflective practices, where the teacher needs to integrate personal and professional knowledge as the situation demands.

• Cross-Cultural Studies
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• v.29
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• pp.201-232
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• 2012

In the world history in the rein of totalitarianism cultural project of government had been activated, and consequently of it official culture had been organized. But at the same time on the other side of it people('narod'), who didn't have cultural means for active expression of own opinion on the reality, had expressed world-view and judgement informally in everyday language. In the literature of autocracy, subjected to censorship, had been expressed and fixed mythically idealized image of sovereign and his works. But in the folklore the image of ruler had been created by liberal fantasy of people. This article examined russian literature and folklore texts of 18 century, when russian people suffered from rapid and dramatic changes, caused by Peter I. Although russian literature of 18 century had gone over to the new literary regime, it still accepted political mechanism as dominant of age, and consequently in the literary texts of this century Peter I was represented as ideal person and great monarch. But various images in folklore texts show that people's opinion on ruler and his activities couldn't be controlled. In other worlds, diverse images of Peter I in folklore texts reflect clear and plain historical consciousness of people. This analysis reveals not only difference between mechanism of idealization of government and historical consciousness of people, but also meaning of cultural memory as indicator of historical reality.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.1
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• pp.197-200
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• 2002

Seborrheic dermatitis is acute or chronic inflammatory disease frequently caused by heredtary factor, endocrine abnormality, alcohol, etc. and characterized by red spots with clear boundary itching. It is similar to Myunyoupung in Oriental Medicine. I prescribed the Seungmahwangryun-tang(升麻黃連湯) and Zowiseunggi-tang(調胃承氣湯) to a patient with Seborrheic dermatitis. After taking above medicines. the patient was cured.

• Journal of the Korean Vacuum Society
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• v.2 no.4
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• pp.515-519
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• 1993

Image processin software is developed to get spot intensity form the frame of a LEEd pattern obtained by using a CCD Camera and a frame grabber. Imporved algorithm for more reasonable background substraction is implemented in this software . I/V Charateristicsof some spots form Cu(001) suface are collected . These results are compared with those of Davis and Noonan and found to be consistent with the latter results. This software is also applied to meausre RHEEd spot intensity oscillatin, and gives clear oscillations very easily.

• Journal of the Korean Society of Safety
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• v.9 no.1
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• pp.56-60
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• 1994

In this study, Cuttent vs. Temperature characteristics of polyethylene with high-voltage treatment and crystallinity have been studied. The current curve( $I_{th}$) shows two peaks at 85 ($^{\circ}C$) and 50($^{\circ}C$), respectively. Trapping of carriers Proceeds during the high-field treatment, and it Is clear that 1th arises from the drift of carriers under the external voltage( $V_{b}$). From the results of TSC of BDPE and LDPE. It is realized that the traps are relation to the crystallinity.y.y.