• 한국정밀공학회지
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• 제15권8호
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• pp.17-25
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• 1998

Aluminum alloys have low density, relatively high strength and yield strength, good plasticity, good machinability, and high corrosion and acid resistance. Therefore, they are suitable for large containers for the food, chemical and other industries. Large containers are often bodies of revolution consisting of shell courses, stiffening rings, heads and other elements joined by annular welds. Larger containers have longer welds and require greater leak-tightness and higher weld mechanical properties. The LNG tank consists of aluminum plates with various sizes, so its construction should by divided by several sections. Moreover, each section has its own sub-section consisted of several aluminum plates. To guarantee the quality of huge LNG tank, therefore, the precise control of plate dimension should by urgently needed in conjunction with the appropriate selection of process parameters such as cutting speed, depth of cut, rotational speed and so on. In this paper, a manufacturing system was developed to implement automatic circular tracking in height direction and automatic circular interpolation in depth of cut direction. Also, the neural network based on the backpropagation algorithm was used to predict the cutting quality and motor load related with the life time of the developed system. It was revealed that the manufacturing system and the neural network could be effectively applied to the bevelling process and to predict the quality of machined area and the motor load.

• 한국실내디자인학회논문집
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• 제23권3호
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• pp.21-28
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• 2014

The purpose of this study is to analysis the change of rural house type in Gyeongbuk province. There are 13 Gun(a kind of administrative district) areas in Gyeongbuk province. According to definition of rural area, the scopes of the research of rural houses limited the 12 places rural area(Gun area, excluded Ulleung-Gun) of Gyeongbuk province. The method of study is to compare and analyze about housing situation, structure of house, housing type and housing area etc. through the statistical data of each Gun area and other various data etc. during these 5 years. As a results of the analysis : 1) The supply ratio of housing is steadily decreasing in rural areas. 2) The houses of rural areas are changing from a detached house to multi-household house and small apartment by development near the rural area. 3) The number and area of commercial buildings are gradually increasing because of urbanization of rural areas. 4) The most houses inside area scopes in the rural area was from $60m^2$ to $85m^2$ area. And the family types of rural house are changing from large family to nuclear family and single households. 5) The structure of rural houses is changing from the brick house type to lightweight steel construction house because of cost-cutting of construction and easy way to construct etc.

• 한국전자파학회논문지
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• 제28권2호
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• pp.155-158
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• 2017

전자, 통신 기술의 발달로 대부분의 장소에서 전자기기가 존재한다. 자동차, 열차, 항공기 등 다양한 장소에서 전자기기의 활용이 증가된 만큼 고출력 전자기파로 인한 오작동과 하드웨어의 치명적인 손상을 확인할 수 있는 안전성을 연구하는 것이 중요하게 되었다. 구조물 내부에 전자기기 및 여러 센서를 연결하는 케이블은 전자기파에 의한 오작동을 초래할 수 있는 원인 중 하나이기 때문에 전자파 영향에 대한 해석이 필수적이다. 본 논문에서는 상관관계 함수와 전송이론을 이용하여, 전기적으로 큰 공진기 내부에 존재하는 케이블에 유기되는 전류를 계산해 외부 전자기파에 의한 영향을 해석하였다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제9권2호
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• pp.127-131
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• 2004

A low-cost, simple strip reader system using a linear movement mechanism of CD-ROM deck has been developed to characterize a lateral flow membrane-based immunochromatographic assay. The test strip reader was assembled by a CD-ROM deck and home-made optical head especially designed for immunoassays. The optical head for detecting reflected light from the test strip surface consists of green light-emitting diode, large area silicon photodiode, and anodized aluminum mounting block providing a slit structure for cutting light from the LED. The stepping motor of the deck was operated in the full step mode, whose distance of each reading point is about 0.15mm. The performance of the strip reader was tested by analysis of HBV(hepatitis B virus) antigen test kit. This strip reader can be useful for inexpensive, disposable, and membrane-based assays that provide visual evidence of the presence of an analyte in a liquid sample.

• 오토저널
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• 제15권3호
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• pp.120-125
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• 1993

The surface roughness of workpiece is reduced during spark-out. The reduction of roughness is a benefit of spark-out, but spark-out lowers productivity. The characteristics of spark-out are different to those of plunge grinding to which feed is applied. This difference is due to overlapping cutting during spark-out. Effect of spark-out is in proportion to volume of grain wear. This phenomenon is due to different overlapping area. Dressing interval can be enlarged by spark-out, when volume of grain wear is large. In this study, the characteristic of spark-out was studied by spark-out obserbation in various grinding conditions. For this purpose thrust force, spark-out time and surface roughness of workpiece were experimentally investigated in various grinding conditions.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.203-203
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• 2012

The SWCNTs network are formed on various plastic substrates such as poly(ethylene terephthalate) (PET), polyimide (PI) and soda lime glass using roll-to-roll printing and spray process. Selective patterning of carbon nanotubes film on transparent substrates was performed using a femtosecond laser. This process has many advantages because it is performed without chemicals and is easily applied to large-area patterning. It could also control the transparency and conductivity of CNT film by selective removal of CNTs. Furthermore, selective cutting of carbon nanotube using a femtosecond laser does not cause any phase change in the CNTs, as usually shown in focused ion beam irradiation of the CNTs. The patterned SWCNT films on transparent substrate can be used electrode layer for touch panels of flexible or flat panel display instead indium tin oxide (ITO) film.

• 대한기계학회논문집
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• 제19권1호
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• pp.22-37
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• 1995

Industrial robot has played a central role in the production automation such as welding, assembling, and painting. There has been, however, little effort to the application of robots in machining work(grinding, cutting, milling, etc.) which is typical 3D work. The machining automation requires a high stiffness robot arm to reduce deformation and vibration. Conventional articulated robots have serially connecting links from the base to the gripper. So, they have very weak structure for he machining work. Stewart Platform is a typical parallel robotic mechanism with a very high stiffness but it has a small work space and a large installation space. This research proposes a new machining robot arm with a double parallel mechanism. It is composed of two platforms and a central axis. The central axis will connect the motions between the first and the second platforms. Therefore, the robot has a large range of work space as well as a high stiffness. This paper will introduce the machining work using the robot and design the proposed robot arm.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 사면안정학술발표회
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• pp.65-81
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• 2003

During the last few decades in Korea, the development of hillside or mountain areas has rapidly increased for infrastructure construction such as railroads, highways and housing. Many landslides have occurred during these constructions. Also, the amount and scale of damage caused by landslides have increased every year. In the case of Far East Asia including Korea, the damage of landslides is consequently reported during the wet season. In this paper, the effect of stabilizing piles on slope stability is checked and the behavior of slope soil and piles are observed throughout the year by field measurements in the large-scale cut slopes. In particular a large-scale cut slope situated on the construction site for the express highway in Donghae, Korea. First of all, The behavior of the slope soil was measured by inclinometers during slope modification. Landslides occurred in this area due to the soil cutting for slope modification. The horizontal deformations of slope soil gradually increased and rapidly decreased at depth of sliding surface indicating that the depth of sliding surface below the ground surface can be predicted. On the basis of being able to predict the depth of the sliding surface, stabilizing piles were designed and constructed in this slope. To ensure the stability of the reinforced slope using stabilizing piles, an instrumentation system was installed. The maximum deflection of piles is measured at the pile head and it is noted that the piles deform like deflection on a cantilever beam. The maximum bending stress of piles is measured at the soil layer. The pile above the soil layer is subjected to lateral earth pressure due to driving force of the slope, while pile below soil layer is subjected to subgrade reaction against pile deflection. As a result of research, the effect and applicability of stabilizing piles in large-scale cut slopes could be confirmed sufficiently.

• 지질공학
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• 제19권2호
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• pp.191-203
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• 2009

본 연구에서는 대규모 절개사면에서 억지말뚝의 효과를 확인하고, 사면과 억지말뚝의 거동을 조사하였다. 먼저, 사면의 절토공사시 경사계를 이용하여 사면지반의 거동을 조사하였다. 계측결과 사면지반의 수평변위는 점차적으로 증가하고, 사면활동면의 발생위치에서 급격히 감소하는 것으로 나타났다. 이를 통하여 사면활동깊이의 예측이 가능하였다. 사면활동면의 예측을 통하여 억지말뚝의 설계와 시공이 수행되었다. 그리고 억지말뚝으로 보강된 절개사면에 대하여 각종 계측시스템을 적용하여 억지말뚝의 거동을 조사하였다. 계측결과 억지말뚝의 수평변위는 켄틸레버보의 변형형상과 유사하게 발생되었으며, 말뚝두부의 철근콘크리트보의 설치로 인하여 두부의 수평변위 억제효과를 확인할 수 있다. 억지말뚝의 최대휨응력이 발생되는 깊이는 대상지반의 상부토사층이 존재하는 깊이와 유사한 것으로 나타났다. 또한, 쏘일네일링 시공을 위한 억지말뚝 전면부 사면굴착시 억지말뚝의 수평변위가 증가함을 알 수 있다. 본 연구를 통하여 대규모 절개사면에 대하여 억지말뚝의 적용성 및 효과를 확인할 수 있다.

• 한국산학기술학회논문지
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• 제10권1호
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• pp.39-45
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• 2009

디스플레이 장치에서 기존의 CRT는 곡면이며 무겁고 큰 부피 때문에 LCD, PDP와 같은 평판디스플레이(FPD)로 대체되고 있다. FPD는 $0.6{\sim}0.8mm$ 두께의 대면적 글래스에 여러 공정을 거친 후에 최종 제품 규격으로 절단하여 제작하기 때문에 글래스의 면적이 크면 클수록 FPD의 생산성이 높다는 밀접한 관계를 갖는다. 따라서 FPD 제조 업계에서는 글래스 면적을 증가시키기 위하여 노력하고 있다. 7세대 글라스($2,220mm\;{\times}\;1,870mm\;{\times}\;0.7mm$)를 대상으로 유한요소해석 및 유동해석을 통하여 이송장치, 배급장치, 수평/경사 변환장치 및 제어장치로 구성된 비접촉 공기부상 이송시스템을 개발하였다. 본 개발에서 확보한 설계기술을 통하여 글라스의 크기가 대형화 되더라도 관련 이송장비를 보다 쉽게 제작하여 적용할 수 있다.