• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.53-55
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• 1996

In this paper, we analyze control methods and structures of AC arc-welders, which is a prerequisite to develop a low-cost and high accurate welder. By using the finite element methods, three types of AC an-welders, movable-core, movable-coil, and saturated-reactor type, are modeled and characterized in the coupled domain of electro-magnetic system.

• 물과 미래
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• 제15권4호
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• pp.31-37
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• 1982

본 연구는 매빈 지형변동에 관한 이동상 수리모형실험에 있어서의 난점인 매상저질축척 및 시간축척을 결정하는 방법을 제안하고 이 상사율에 의해 현지와 재현성이 좋은 실험결과를 얻었다.

• 한국정밀공학회지
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• 제10권1호
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• pp.114-125
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• 1993

Thermoelastoplastic analysis of a typical device consisting of fixed tube and movable case having an inital clearance in between, which is subjected to pressure and thermal load, has been carried out to examine the cause of malfunction mainly at high temperature condition, and to improve the design. Stresses, deformed shape, interface state and their effects on normal function of case are discussed by using finite element method. The extraction energy can be remarkably reduced by changing the configuration of tube from the present design (Parallel type) to the improved design (Tapered type). This effect has been proved by sustained cyclic function test.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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• pp.207-210
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• 2008

본 논문에서는 램제트 기관의 성능을 결정짓는 공기흡입구를 램제트 엔진의 비행 목적에 맞게 비행 마하속도 4에서 기본설계를 수행하였다. 순항고도 12km, Mach $2{\sim}6$의 넓은 영역에서의 운용을 가능하게 하기 위하여 가변형 공기흡입구의 개념을 도입하였다.

• 한국소음진동공학회논문집
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• 제25권1호
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• pp.58-64
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• 2015

There are a lot of different types of noise from construction site and it depends on construction stage, equipment type and number of operating equipments. The problem is that the almost noise from construction site is high level and some kinds of noise levels are over 100 dB. In addition, if construction site is located in downtown, there are a few options to reduce noise level. Therefore several site mitigation plans were developed to reduce different types of construction noises such as breaker work, gang form and asphalt saw. They were applied in site and evaluated noise reduction performance. The test result of site insertion loss was between 4~8 dB depends on the equipment and type of work.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.445-446
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• 2012

• 설비공학논문집
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• 제28권9호
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• pp.343-349
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• 2016

Due to the recent increase in lighting energy consumption in buildings, there are a growing number of studies seeking solutions this problem. The effectiveness of light-shelves as natural lighting systems to solve this problem has been recognized, and various studies regarding such systems are being carried out currently. However, the lighting efficiency of light-shelves decreases if illumination intensity is low-such as at night time, and it also obstructs the views of building occupants. Therefore, the purpose of this study is to examine a movable drawer type light-shelf which allows for the width of the reflector to be adjusted and verify its performance through a simulated test-bed. The following conclusions were reached. 1) The purpose of this study is to solve the problem previously associated with the light-shelf system- of obstructed views-by responding to external environments and minimizing the width of the light-shelf at night time when the efficiency of the light-shelf declines. 2) The proper variables of the movable drawer type light-shelf which enables the width adjustment of the reflector were ascertained in this study according to four solar terms : a width of 0.6 m at an angle of $20^{\circ}$, a width of 0.4m with an angle of $20^{\circ}$, and a width of 0.1 m with an angle of $20^{\circ}$ were determined for the summer solstice, fall/spring equinoxes, and winter solstice respectively; revealing that width adjustment of the light-shelf is a significant factor. 3) The movable drawer type light-shelf which enables${\backslash}$width adjustment of the reflector suggested in this study can reduce the lighting energy consumption by 18.7% and 14.3% in comparison to previous light-shelves with a fixed width of 0.3 m and 0.6m, indicating that it is effective for saving energy.

• 생물환경조절학회지
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• 제4권2호
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• pp.167-174
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• 1995

This study was carried out to find a way of improving the windproof capability of greenhouse foundations. Generally, greenhouses are often collapsed due to the strong winds, because they are very light weight structures. In such a critical situations, the foundations are very often subjected to uplift and vibration at the same time. This paper describes both the wind disaster of greenhouses by the typhoon FAEY and the uplift resistance of greenhouse foundations. Followings are the results obtained from this study ; Judging from the view point of year round cultural aspects, it is recommended that some measures be taken for the preventions of greenhouse film ruptures because greenhouse structural damages are found to be directly associated with the local rupture of cover film. In the case of surveyed area, movable pipe-houses or pipe-houses of 1-2W type were found to be completely destroyed when the maximum instantaneous wind velocity was over 30m/sec or so. In the case of movable pipe-houses, the uplift resistance of greenhouse was expected to increase with the increase of pipe diameter and/or the embedment pipe length. But at present situations there is a limitation in raising the uplift resistance of movable pipe-house, because pipe diameters as well as pipe lengths customarily selected by farmers are quite a much limited.

• Journal of Power Electronics
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• 제15권6호
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• pp.1654-1663
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• 2015

Compared to LC resonance, LCL resonance has distinct advantages such as a large resonant capability, low voltage and current stresses of the power device, constant voltage or current output characteristics, and fault-tolerance capability. Thus, LCL resonant compensation is employed for a movable Inductive Contactless Power Transfer (ICPT) system with a multi-load in this paper, which achieves constant current output characteristics. Peculiarly, the primary side adopts a much larger compensation inductor than the primary leakage inductor to lower the reactive power, reduce the input current ripple, generate a large current in the primary side, and realize soft-switching. Furthermore, this paper proposes an approximate resonant point for large inductor-ratio LCL resonant compensation through fundamental wave analysis. In addition, the PWM control strategy is used for this system to achieve constant current output characteristics. Finally, an experimental platform is built, whose secondary E-Type coils can ride and move on a primary rail. Simulations and experiments are conducted to verify the effectiveness and accuracy of both the theory and the design method.

• 한국도서관정보학회지
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• 제50권4호
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• pp.305-337
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• 2019

연구는 경상남도 의령지역에서 간행된 109종의 문집을 대상으로 문집 간행의 구체적인 양상과 출판문화적 의미를 파악하고자 문집의 판종, 유형, 저자사항, 간행사항을 분석하였다. 연구의 결과 다음과 같은 사실이 밝혀졌다. 경남 의령지역 간행 문집 109종의 판종, 유형, 저자사항, 간행사항을 분석한 결과는 다음과 같다. 1) 판종은 목활자본(52종, 47.7%), 석판본(25종, 22.9%), 신연활자본(18종, 16.5%), 목판본(14종, 12.8%)의 순이다. 2) 유형은 문집(53종, 48.6%), 유집(47종, 43.1%), 실기(9종, 8.3%)의 순이다. 3) 문집 저자의 출생연도는 1318년부터 1902년까지 584년의 간극이 있다. 1318년생은 <경은실기>의 저자인 전조생이고, 1902년생은 <회동유고>의 저자인 전용기(1902-1978)이다. 전체 저자 104명 가운데 19세기 전기 출생자가 16명(15.4%), 19세기 후기 출생자가 54명(51.9%)로서 19세기에는 전체의 67.3%에 해당하는 70명이 출생하였다. 4) 109종 문집 저자의 성관은 모두 29개로서 담양전씨(15종) > 고성이씨(12종) > 진양강씨·탐잔안씨(각9종)의 순이다. 5) 의령에서 문집의 간행년도를 보면, 1610년대부터 1980년대까지 370년간 간행되었고, 1820년대까지는 문집이 목판으로만 간행되었고, 1850년대에 목활자본 문집이 처음 나타나며, 1930년대에 석판본, 신연활자본 문집이 나타난다. 6) 저자 사후 문집간행에 소요되는 기간을 살펴보면. 저자가 별세하는 당해년부터 사후 545년까지 간행되었고, 저자 사후 50년 이내에 63%인 69종이 간행되었다. 7) 문집의 간행소는 판종에 구분없이 조상의 제향공간인 누정과 재실에서 가장 많이 간행되었다. 이는 문집간행이 선조의 학문과 행적을 선양하고자 하는 혈연공동체의 사업이었음을 말해준다.