• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.231-235
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• 1989

Possibility of using microcarriers for the growth of a transformed human embryonic kidney cell line 293 was investigated. The cell grew well in a static culture such as T-flasks with medium of DME/F12 (3:1) mixture supplemented with 5% FBS, but it was most difficult to make the cells grow on microcarriers mainly due to the low attachment efficiency and poor spreading at initial stage of the culture. Consequently, 30-50% of the cells were lost upon inoculation into microcarrier suspension and significant fraction of the mirrocarrier became bald. The medium supplemented with the concentrated conditioned medium by hepatoma cell line HpG2 supported the active growth of the cells on microcarrier and the cells showed a very healthy and well spreading morphology. It was probable that some spreading and attachment factors of HpG2 conditioned medium were effective for 293 cells.

• Journal of Korean Association for Spatial Structures
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• v.7 no.2 s.24
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• pp.83-90
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• 2007

Buildings become high and large. CFT(Concrete Filled steel Tube) columns have been developed to manage effectively that loads which columns support and cross sections of columns are increased. Because CFT column is the composite structure made of two different materials, many researches have been performed to look into mechanical behaviors. This study is an analytic study about bond stress on interface between concrete core and steel tube in circular and rectangular CFT columns. ABAQUS/Standard Version 5.8 is used to analyze bond stress by bond form and position of shear-connector, and improved analystic method about mechanical characters on interface is suggested.

• Journal of the KSME
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• v.32 no.8
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• pp.673-684
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• 1992

전광 통신의 시대를 맞이하면서 광섬유의 수요가 급증하고 있어 보다 질 좋고 생산 단가가 절 감된 광섬유의 제조가 중요하며 이것은 기존 기술의 최적화와 새로운 제조기술의 개발에 의하 여만 가능할 것이다. 생산성 및 광섬유의 질이 화학증착을 비롯한 각 공정에 의지하므로 각 공 정의 최적화가 중요하며 광섬유 제조 화학증착과정에서 층착 성능은 thermophoresis로써 결정지 어지는 입자운동 및 부착에 의지하므로 향상된 증착 성능을 얻기 위하여서는 각과정에서의 열 전달, 유체유동 및 입자 부착 해석이 선행되어야 한다. 증착의 균일성, 증착효율 및 증착률의 향상을 위한 노력은 모델링을 포함한 실험적 연구 및 새로운 기술의 개발 및 시도가 필요하다고 할 수 있다.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.33-34
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• 2011

본 논문은 900MHz 대역의 RFID를 이용하여 고속도로 자동 요금징수 시스템을 개발하고, 차량에 부착한 태그를 RFID 리더가 인식하는 효율을 높이기 위하여 최적의 태그부착위치와 안테나 설치위치에 대하여 연구하고 속도에 따른 인식률을 연구 하였다.

• KAPE Magazine
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• s.158
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• pp.4-5
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• 2009

오는 2011년부터 부산물을 포함한 수입되는 모든 쇠고기에 대해 12자리의 유통식별번호가 부여되며 유통되는 모든 수입쇠고기 포장박스에는 바코드 형식의 유통식별번호표가 부착된다. 유통식별번호표는 업무의 효율성을 감안해 현행 수입쇠고기 포장 박스에 부착되고 있는 한글표시사항과 함께 표기되는 방안이 검토된다. 즉, 거래명세서 발급 및 거래내역서 서류 작성 보관시 B/L(선하증권) 번호를 포함토록 하고 수입쇠고기 보관 판매시 B/L 번호 표시를 의무화했던 현행 수입쇠고기 유통이력관리 제도가 대대적으로 손질보다 강화된 방식으로 개편되는 것이다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.04a
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• pp.20-20
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• 1998

적 잠수함을 탐지했을 때 적 잠수함이 10km 이내의 거리에서는 어뢰에 부착된 선체 부착형 능동소나로 적 잠수함을 추적하여 직접 공격하는 방법이 효과적이다. 그러나 10km에서 19km 정도의 거리인 경우에는 로켓트를 이용하여 어뢰를 목표지점까지 운반하고 운반된 어뢰가 바닷속에 착수하면 수동예인 음탕기(TASS)로 적 잠수함을 탐지 추적하는 체계가 효율적이다. 19km 이상이 되면 헬기로 적 잠수함을 탐지하고 목표지점에 어뢰를 투하시키는 방안이 일반적으로 운용되고 있다. 그러나 최근에는 50km 정도까지도 유도탄으로 어뢰를 운반하는 체계가 선호되어 적용되고 있기도 하다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3A
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• pp.555-563
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• 2006

Recently, many bridges become not only functionally obsolete of bridge deck due to inadequate width but also structurally deficient of substructure due to erosion. In these cases, widening is almost always more economical than complete replacement, and therefore there is a need to make available the results of research and field experience pertaining to the widening of bridge substructure. But, an experimental study for the guarantee of unification between existing and new substructure with adhesive anchor is so insufficient that the development of adhesive anchor system for the unification should be settled promptly. The purpose of the present study is to explore pull out and shear characteristics of adhesive anchor system. For this purpose, several series of concrete specimens have been tested. Major test variables were the bonded length, anchor diameter and anchor slope. The pull out strength, bond stress and shear strength of adhesive faces were measured for the specimens. The present study indicates that the pull out strength increased with more bonded length and more anchor diameter, and that the bond stress decreased with more bonded length and more anchor diameter. The pull out strength and the bond stress increases with more anchor slope and it is considered that the slope of $5^{\circ}$ was more efficient. From the shear tests, it is supposed that anchor diameters more than D19 was proper to the adhesive anchor. Finally, it is expected that both experimental data in these tests and further study including mock-up tests will contribute to the establishment of the unification between existing and new substructure with adhesive anchor.

• Journal of Environmental Impact Assessment
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• v.27 no.6
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• pp.595-603
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• 2018

This study was conducted to understand the growth of attached microbial community in small and medium streams of Gyeonggi-do and the removal efficiency of fluoride with changes in growth. The sites monitoring were carried out for 12 weeks at the P1 and P2(P1 is the point where the discharge water flows. P2 is the downstream point of about 2 km flow), and investigated the water quality and the biomass analysis of the attached microbial community. The growth of the attached microbial community increased up to the 7th investigation, and it was observed that detachment phenomenon occurred. Influencing factors about growth of the attached microbial community were flow rate, velocity, and organic material(T-N & T-P). Meanwhile, fluoride content of attached microbial community also tended to increase until the 7th investigation, and decrease from the 8th. It is assumed that fluoride content has also be reduced with the detachment phenomenon of the attached microbial community. It is expected that this will contribute to the evaluation and management of the use of attached microbial community as a means of stream management. The application of techniques using the attached microbial community should include basic investigation of factors that may affect the growth of the attached microbial community and replacement of the attachment plate according to the time of removal.

• The Journal of the Acoustical Society of Korea
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• v.17 no.2
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• pp.25-31
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• 1998

본 연구에서는 자동차 유리판에 초음파 대역 진동을 효율적으로 발생시킬 수 있는 압전 액츄에이터를 개발하고자 하였다. 자동차 유리판을 단순지지 평판으로 가정하였으며, 액츄에이터로는 PZT 진동자를 사용하였다. 유한 요소법(Finite Element Method)을 통하여 유리판의 최적 공진 주파수와 유리판에 부착할 압전 진동자의 구조 조건인 최적 위치와 개 수를 결정하였다. 설계 결과에 따라 자동차 유리판에 압전 진동자를 부착하여 임펄스 응답 해석(impulse response analysis)과 임피던스 해석(impedance analysis)을 수행하여 구동 주 파수를 확인하였다. 그 결과, 이 주파수로 가진하여 유리판 전면에 걸쳐 고른 초음파 진동이 분포함을 확인하였으며, 나아가 전기적 임피던스 매칭(impedance matching)을 통해 더 큰 효율의 진동을 발생시킬 수 있었다.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.2
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• pp.258-263
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• 2011

This study is aimed at obtaining basic design data for Savonius wind turbine, available in the domestic wind environments. To the end, the flow field characteristics around the wind turbine attached with 1/4 wind shield were monitored along with numerical analysis. On the top of this, numerical analysis and experiments on the rpm of the turbine rotor were conducted. As a result, this study found that the numerical analysis results squares with the experiment results and the rpm improves by over 70%.