• 수산경영론집
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• 제13권2호
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• pp.31-48
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• 1982

Though modern banking organs were established in Korea with the Kanghwa Treaty as a momentum, the benefit of financing at that time, which was mainly given to merchants and industrialists and traders, was extremely limited to the fishermen. The fishermen who were out of favor with the benefit of financing of modern banking organs were forced to rely on high interest loans, a category of usury capital, issued by the middlemen (the Kaekju) who lent them the deficit of their necessary funds. The fact was that in the field of fisheries the middlemen who issued usury capital played the leading part in fisheries financing of the Late Yi Dynasty. The middlemen, however, sqeezed a part or all of surplus products and on occasion even necessary products out of the fishermen by means of outward compulsion of economy. Moreover they put the fishermen further in trouble by putting-out system. In order to keep on with the production of aquatic products, the fishermen with little capital and no property established the antinomic rotations with the middlemen whose disadvantageous terms they were inevitably to accept. Thus the middlemen who did business with the fishermen exercised their authority over them, securing a strong activity foundation in the field of fisheries. But the traditional form of the Kaekiu was transformed and gradually declined in the field of fisheries according as the market rules were proclaimed in 1914.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권5호
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• pp.204-210
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• 2005

Alternating current (AC) losses of two Bi-2223 ([Bi, Pb]: Sr: Ca: Cu: O = 2:2:2:3) tapes [(Tape I, un-twist-pitch) and the other with a twist-pitch of 10 mm (Tape II)] were measured and compared. These samples, produced by the powder-in-(Ag) tube (PIT) method, are multi-filamentary. Also, it's produced by non-twist and different twist pitch (8, 10, 13, 30, 50 and 70 mm). The critical current measurement was carried out under the environment in liquid Nitrogen and in zero-field by 4-probe method. Susceptibility measurements were conducted while cooling in a magnetic field. Flux loss measurements were conducted as a function of ramping rate, frequency and field direction. The AC flux loss increases as the twist-pitch of the tapes decreased, in agreement with the Norris Equation. Neutron-diffraction measurements have been carried out investigate the crystal structure, magnetic structures, and magnetic phase transitions in Bi-2223([Bi, Pb]:Sr:Ca:Cu:O)

• 레미콘
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• 7호통권68호
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• pp.9-16
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• 2001

Execution of exposed concrete has some problems such as segregation, surface honey comb and insufficient surface flossing due to unsuitable mix proportion and unfavorable construction in our field. Therefore, in this paper, field application of exposed concrete at training center building of Chongju university in Daecheon are carried out based on the mixing data obtained from laboratory test. Base concrete are made in accordance with mixing data. Segregation reducing type superplasticizer developed are applied in order to flow the vase concrete with out segregation of materials. According to test results, air content shows to be reduced after flowing. Compressive strength of flowing concrete is higher than that of base concrete about 7%. Surface glossing is reducing as the age goes on. It is improved about 10% compared to that of vase concrete.

• Nuclear Engineering and Technology
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• 제8권1호
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• pp.29-40
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• 1976

시리콘 태양전지의 한쪽 면내에서 광에 의해서 발생된 전하운반체의 수집을 하는데 있어서 부가적인 도움을 줄 수 있는 정전적인 부등전계 효과에 고나한 연구가 수행되었다. 주석(tin) 주입에서 오는 격자변형의 보상효과로 말미암아 P형 측내에 보론농도의 구배를 가져오므로서 부동전계를 발생시킬 수 있었다. 태양전지내에 p-n 접합을 gtud성시키기 위하여 주로 방사증식확산의 원리에 근거를 둔 새로운 이온주입법이 채택되었다. 이온주입으로 된 태양전지의 회로개방전압과 변환효율을 각각 0.44V 및 5%였다.

• 천문학회보
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• 제35권1호
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• pp.26.2-26.2
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• 2010

It has been a puzzle in solar physics how a low-lying magnetic structure such as a solar prominence surrounded by a strongly line-tied overlying field sometimes intrudes through the latter and goes into eruption. A numerical simulation study of the solar coronal plasma reveals that a ballooning instability can explain this type of eruptive process. We consider an idealized situation with two flux ropes merging. When magnetic field lines from different flux ropes reconnect, a new field line connecting farther footpoints is generated. Since the field line length abruptly increases, the field line expands outward. If the plasma beta is low, this expansion takes place more or less evenly over the whole field line. If, on the other hand, the plasma beta is high enough somewhere in this field line, the outward expansion is not even, but is localized as in a bulging balloon. This ballooning section of the magnetic field penetrates out of the overlying field, and eventually the originally underlying field and the overlying field come to interchange their apex positions. This process may explain how a field structure that has stably been confined by an overlying field can occasionally show a localized eruptive behavior.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2210-2211
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• 2011

Load capacity varies according to a day of the week in traction power supply system, because time schedule in railway is changed as demand for passengers and freights. Therefore, Voltage drop also varies as load capacity. In Korea railway, Voltage collected from catenary in train is decreased, as load supplied traction power supply system is increased. Therefore, investigation about voltage drop should be performed, before development of countermeasure against voltage drop. The investigation can be performed by simulation or field test. Naturally, field test is more precise than simulation. In addition, field test should be carried out at peak load. This paper presents test and analysis about voltage drop in railway. The test is performed in both a day of the week and weekend. The analysis is figured out comparison load capacity between two days and voltage drop across terminal.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.1360-1364
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• 2009

Necessity of removable soil nailing has been arisen in the soil nailing system because of problem such as civil petition for geotechnical environment and invasion of the ground boundary line and payments for use besides geotechnical engineering. Removable soil nailing system is improved soil nailing system that fixed socket arranged in boring hole for increasement of skin friction. In this study, field pull-out tests are carried out more 4 times considering installed distance of fixed socket and analyze skin friction behavior characteristics in fixed socket through analysis of measurements of strain gauge attached to fixed socket. Also, to evaluate application for wedge type removable soil nailing system analyzing displacement aspects through field pull-out tests by trial construction.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.940-947
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• 2011

Load capacity varies according to a day of the week in traction power supply system, because time schedule in railway is changed as demand for passengers and freights. Therefore, Voltage drop also varies as load capacity. In Korea railway, Voltage collected from catenary in train is decreased, as load supplied traction power supply system is increased. Therefore, investigation about voltage drop should be performed, before development of countermeasure against voltage drop. The investigation can be performed by simulation or field test. Naturally, field test is more precise than simulation. In addition, field test should be carried out at peak load. This paper presents test and analysis about voltage drop in railway. The test is performed in both a day of the week and weekend. The analysis is figured out comparison load capacity between two days and voltage drop across terminal.

• Journal of Magnetics
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• 제20권1호
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• pp.8-10
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• 2015

The magnetic anisotropy field plays an important role in spin-orbit-torque-induced magnetization dynamics with electric current injection. Here, we propose a magnetometric technique to measure the magnetic anisotropy field in nanostructured ferromagnetic thin films. This technique utilizes a magneto-optical Kerr effect microscope equipped with two-axis electromagnets. By measuring the out-of-plane hysteresis loops and then analyzing their saturated magnetization with respect to the in-plane magnetic field, the magnetic anisotropy field is uniquely quantified within the context of the Stoner-Wohlfarth theory. The present technique can be applied to small nanostructures, enabling in-situ determination of the magnetic anisotropy field of nanodevices.

• 한국과학교육학회지
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• 제1권1호
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• pp.45-52
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• 1978

In order to normalized the Earth Science Education, experiments and geologic field trainings are very important. But it have not carried out on account of many difficulties in current High School of Korea. These difficulties are lack of time, many problems of the text book, heavy teaching load, shortage of facilities and experimental equipments, and poor quality of teacher etc. The practical training of geologic field trip is very important in Earth Science Education. Finally, wirter propose a new teaching plan of geologic field training as follows: 1. The teacher must prepare the guide paper of field geologic training. 2. Subjects of practical training must simplify. 3. The teacher must take a pre-field investigation in order to get the teaching plan and the preparation of practical field training. 4. Let students observe for themselves on this guide, as if they were geologists. 5. The teacher must conclude about practical training after the working.