• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.3
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• pp.294-301
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• 1996

To improve the corrosion resistance of stainless steel and Fe, the adherence between fIlm and substarte and the corrosion resistance to ceramic fIlm ($TiO_2$ and $ZrO_2$), coated by RF magnetron sputtering, were studied. The adherence index (X) was determined by the measure of micro - hardness test. Also, the corrosion resistance on oxide coatings was studied using electrochemical measurement. The main results obtained are as the following: 1) In the micro - hardness test, with 1J.UI1 thickness fIlm, it has only one the value of X. Above 2J.UI1 thickness fIlm, however, get another value ofX as the cracks in fIlm. 2) The adhensivity of titania ($TiO_2$) coated fIlm is superior to that of zirconia ($ZrO_2$) coated fIlm. 3) All oxide fIlm used adhere well on the mild materials such as pure steel than high intensity materials like stainless steel. 4) The corrosion resistance of zirconia coated materials was improved compared to titania coated materials.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.1
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• pp.53-60
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• 2010

In constructing ILM(Incremental Launching Method) bridges, a launching nose is generally used in order to absorb temporary stress occurring during launching. The sectional forces of superstructure of ILM bridges, which occurs during launching, varies significantly according to the length, weight and stiffness of the launching nose. Thus in order to guarantee the safety of section of ILM bridges, the change of stress according to interaction behavior between launching nose and superstructure should be considered. However, the span division and span length are often decided based on previous cases in practice. It makes the design sections of launching nose are similar in spite of different projects. The designer's anxiety to optimize the launching nose to affect the optimum design of superstructure is also weak. In this study, an design formular to optimize the nose is proposed by using the analysis formular of nose-deck interaction and the design level of ILM bridges constructed on 00 Expressway is examined. According to the result of this study, the proposed design formulas are expected to make a significant contribution to section design that is economically efficient and at the same time guarantees the safety of the superstructure and launching noses of ILM bridges regardless of span length.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.404-407
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• 2009

ILM(incremental launching method) 교량공법은 품질확보에 효과적인 프리스트레스 콘크리트 교량공법으로 인정받고 있다. 이 공법에 의해 시공되는 교량의 상부단면은 시공 중에 지간의 중앙부와 지점부에 일시적이나마 모두 위치하게 된다. 앞선 연구에서 압출 중인 ILM 교량의 상부단면에 발생하는 단면력의 변화를 간편하게 예측할 수 있는 해석식을 개발하였다. 그리고 개발된 해석식을 이용하여 매개변수들의 변화에 따른 상호작용의 영향을 분석하여 많은 대안들이 검토되는 초기 설계단계에 유용한 설계식도 제안하였다. 본 논문에서는 압출중인 ILM 교량의 상부단면에 발생하는 단면력을 효과적으로 제어위해 유도된 해석식을 이용하여 현재 국내 공용중인 ILM 교량의 설계수준을 검토하였고, 상부구조의 최적설계를 위한 방안을 제시하였다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.717-720
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• 2010

본 논문에서는 ILM 교량의 특성상 압출 시 응력이 발생하며, 이러한 응력의 발생위치는 본구조물의 캔틸레버화가 되었을 시 나타나게 된다. 이러한 응력을 줄이기 위하여 ILM 교량의 기본설계 과정을 유전자 알고리즘 기법을 이용하여 단면의 형고에 변화를 주어 반복수행 함으로써 최적설계를 도출해 내는 연구를 수행하였다. 유전자 알고리즘을 통하여 교배를 시켜서 세대가 올라갈수록 모멘트는 줄어들고 목적함수는 올라가는 진행 과정을 보여 줌으로써 최적화 과정을 표현하였고, 단면의 형고를 바꿔 줌으로써 ILM 교량의 최적화를 확인할 수가 있었다. 본 연구에서 수행한 유전자 알고리즘을 이용한 최적화 방법을 보여주려고 한다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.459-467
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• 2014

ILM(Incremental Launching Method) bridges pass both the middle of spans and supports during launching. The launching noses are used to minimize the maximum positive moments and negative moments of the superstructure occurring during launching for ILM bridges. In this study, the simplified analysis formula considering diaphragm to calculate the bending moment that occurs during launching is induced and analyzes the optimum design conditions considering diaphragm. The accuracy of the proposed simplified analysis formular compared to the MIDAS Civil has an error of less than 5%. There is a difference up to 13% in the moment between the cases when the diaphragm is considered and is not. In addition, the criteria for deciding the unit weight of equivalent cross section and average stiffness value of equivalent cross section that can be applied to the simplified analysis formula is proposed. In this study, an effective way to optimize the launching nose is proposed that the optimum design is taken in the condition of minimizing the negative moment because of the mechanic characteristic of ILM bridges.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.455-462
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• 2004

The ILM(incremental launching method) bridge, which is one of PS(prestressed) concrete bridge construction methods is widely adopted in Korea owing to its effectiveness for the quality control in construction. The purpose of this study is to analyze the structural behavior of ILM bridge proceeding with tapered sectional launching nose. This study presents basic technical materials to achieve the optimum design for superstructure and launching nose of ILM bridge. First this study introduces an equation to analyze the interaction between launching nose and superstructure. In this process, relative length, weight, and flexural stiffness between launching nose and superstructure are considered as investigating parameters. Second, the effects of superstructure resulting from these parameters is estimated analyzed by using the induced equations.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.737-738
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• 2009

IT 환경이 급속도로 발전해 가고 있다. 기업 내에서 생성 및 보관되는 데이터의 양은 시간이 흐름에 따라 급격히 증가하고 있으며, 기업의 의사결정에 중요한 데이터의 가치는 변화를 거듭한다. 데이터의 증가는 곧 그것을 관리하는 비용의 증가를 불러오고, 방대한 데이터 속에서 진정한 정보의 가치를 창출하는 것이 어려운 상황에 직면해 있다. 이러한 기업의 비즈니스 프로세스에 맞춰 효과적인 ILM(Information Lifecycle Management)의 구현은 반드시 필요하다. 본 연구는 데이터의 가치를 보다 효과적이며 비용 효율적으로 사용할 수 있는 ILM의 구현을 위해 Database 기반의 Archiving System 구축 방법론을 제시하고 이를 바탕으로 실제 ILM이 구현된 기업의 구축 효과 및 성능 평가를 통해 그 타당성에 대하여 연구하는 것을 그 목적으로 한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.529-532
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• 2005

IT 산업의 발달과 함께, 정보의 양은 기하급수적으로 증가하고 있고, 최소의 비용으로 정보의 가치를 최대로 창출하기 위해 서버와 스토리지 간에 대용량 데이터를 고속으로 전송할 수 있는 네트워크인 SAN(Storage Area Networks)의 급속한 발전을 하게 되었다. 이에 따라 네트워크로 연결된 자동화 스토리지 인프라는 물론 포괄적인 서비스 및 솔루션이 결합된 새로운 정보 관리 전략인 ILM(Information Lifecycle Management)이 대두되기 시작했다. 본 논문은 SAN 을 효율적으로 관리할 수 있고, ILM 을 위한 웹 기반 솔루션인 SANCruiser 시스템을 제안한다.

• Fisheries and Aquatic Sciences
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• v.22 no.12
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• pp.30.1-30.11
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• 2019

Marine natural products isolated from the sponge Fascaplysinopsis cf reticulata, in French Polynesia, were investigated as an alternative to antibiotics to control pathogens in aquaculture. The overuse of antibiotics in aquaculture is largely considered to be an environmental pollution, because it supports the transfer of antibiotic resistance genes within the aquatic environment. One environmentally friendly alternative to antibiotics is the use of quorum sensing inhibitors (QSIs). Quorum sensing (QS) is a regulatory mechanism in bacteria which control virulence factors through the secretion of autoinducers (AIs), such as acyl-homoserine lactone (AHL) in gram-negative bacteria. Vibrio harveyi QS is controlled through three parallel pathways: HAI-1, AI-2, and CAI-1. Bioassay-guided purification of F. cf reticulata extract was conducted on two bacterial species, i.e., Tenacibaculum maritimum and V. harveyi for antibiotic and QS inhibition bioactivities. Toxicity bioassay of fractions was also evaluated on the freshwater fish Poecilia reticulata and the marine fish Acanthurus triostegus. Cyclohexanic and dichloromethane fractions of F. cf reticulata exhibited QS inhibition on V. harveyi and antibiotic bioactivities on V. harveyi and T. maritimum, respectively. Palauolide (1) and fascaplysin (2) were purified as major molecules from the cyclohexanic and dichloromethane fractions, respectively. Palauolide inhibited QS of V. harveyi through HAI-1 QS pathway at 50 ㎍ ml^-1 (26 μM), while fascaplysin affected the bacterial growth of V. harveyi (50 ㎍ ml^-1) and T. maritimum (0.25 ㎍). The toxicity of fascaplysin-enriched fraction (FEF) was evaluated and exhibited a toxic effect against fish at 50 ㎍ ml^-1. This study demonstrated for the first time the QSI potential of palauolide (1). Future research may assess the toxicity of both the cyclohexanic fraction of the sponge and palauolide (1) on fish, to confirm their potential as alternative to antibiotics in fish farming.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.3
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• pp.245-258
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• 2012

ILM(incremental launching method) is a way of construction, installing a girder producing spot behind the abutment, making the bridge girder infilled with concrete continuously and launching with using by jack. The superstructure of the bridge constructed by this method is temporarily located on the center of the span and the supporting points under construction. Therefore, the sections are structurally undergone maximum positive moment, maximum negative moment, and maximum shear force arising from self weight. On the other hand, launching nose is attached to the front of the girder to decrease the cantilever effect. The magnitude of this temporary stress creating on the upper section is dependent upon the launching nose's characteristics. This study has proposed an analysis formula simplified on the assumption that the launching nose section is a quasi-equivalent section(rigid; equivalent section, weight; tapered section) in order to ensure the accuracy of the analysis formula and improve its usage with reference to the interaction between the launching nose and the upper section; and a prismatic analysis formula modified by displacing a diaphragm's weight by a concentrated load in order to improve the accuracy of the existing analysis formula that assumes the launching nose section as the equivalent section. To judge the accuracy and usage of two analysis formulas proposed, we have compared and analyzed computational structural analysis programs and existing analysis formulas based on actual ILM bridge data. As a result, all of two reveal the superior accuracy and also their usage has been improved by the simplification of analysis formulas.