• 한국산학기술학회논문지
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• 제13권12호
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• pp.5669-5675
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• 2012

이종궤간(표준줴/광궤)이 존재하는 유라시아 철도네트워크(TKR, TCR 및 TSR)의 화물운송시간 및 비용을 절감하기 위해서는 이 구간을 자유롭게 운행할 수 있는 궤간가변 윤축시스템의 개발이 중요하다. 국내에서는 기존 해외 윤축시스템을 보완하고자 새로운 한국형 궤간가변 윤축시스템을 개발 및 제작중이다. 본 연구에서는 안전-수명설계관점에서 강도와 내구성해석을 수행하였다. 본 시스템의 내구성해석결과로서, 주요부품은 $1{\times}10^7$ 사이클까지 안전하였다. 또한, 주행중 안전성을 확인하기위하여 국제철도규정 UIC에 따라 리그피로시험을 수행하였다. 이 시험을 통하여 본 궤간가변 윤축시스템은 관련 안전규정에 만족함을 확인하였다.

• 한국재난정보학회 논문집
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• 제16권1호
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• pp.10-20
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• 2020

연구목적: 터널구조물 유지관리계측의 현장점검 결과를 분석하여 개선방안을 제시한다. 연구방법: 도심지에서 건설되고 있는 서울지하철◯호선 14개 공구의 터널구조물을 대상으로 유지관리계측에 대한 다양한 항목의 문제점을 조사하고 분석을 실시하였다. 연구결과: 유지관리 계측 항목과 계측수량 및 설치위치는 개착터널과 굴착터널로 구분하여 개선방안을 제시하였다. 계측기기의 내구연한은 각종 기준을 검토하였고, 내구성 확인방법은 계측센서의 승인 및 검수, 검사 및 시험, 검정 및 교정 등의 개선방안을 제시하였다. 결론: 터널구조물 유지관리계측의 개선방안을 건설현장에 적용하면 유지관리계측의 효율성이 증대되고 건설계측 기술발전에 기여할 것이다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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• pp.201-208
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• 2004

To substitute conventional reinforced-concrete bridge deck, glass composite precast bridge deck - Delta Deck/sup TM/, which possesses advantages of light weight, high strength, corrosion resistance and durability, is developed for the DB24 truck load. Pultruded composite bridge deck is designed and fabricated. To verify serviceability and structural safety, finite element analysis, structural testing such as flexural test, local fatigue test, flexural fatigue test and field tests are conducted. In this paper structural characteristics of developed deck and its field application in Korea is presented.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1991년도 봄 학술발표회 논문집
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• pp.117-120
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• 1991

Cracks of concrete structure must be analyzed and estimated synthetically in order to have a maintenance and to insure the safety and the durability of structure. Concrete cracks have to be surveyed with respect to depth, width, shape and direction etc, but crack depth among these items is not measured easily. Occasionally, it needs to measure the crack depth of concrete structure for the purpose of evaulating the safe capacity and the necessity of repair. Therefore, this research is performed to verify the applicability and the accuracy of Ultra-sonic Pulse Velocity Technique(Tester), in non-destructive testing methods of concrete crack depth.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.27-32
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• 1999

This study was performed to evaluate properties of recycled concrete for roadway pavement. Recycled concretes was manufactured for the target compressive strength of 280kg/$\textrm{cm}^2$ and 180kg/$\textrm{cm}^2$ with recycled aggregate ratio of 0%, 20%, 40%, 60%, 80%, respectively. Laboratory experiment was conducted for testing properties of fresh concrete and concrete strength at curing 28days and durability by freezing and thawing treatment. The study result presented a maximum replacement ratio of recycled material.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 가을 학술발표대회 논문집(III)
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• pp.737-742
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• 1998

Non-destructive field tests of the concrete has achieved increasing acceptance for the evaluation of existing concrete structures. But the application of this test has not still accomplished to guarantee perfectly the durability of the concrete bridges in Korea. As two major testing methods, this paper recommends the proper empirical relationship between the rebound number together with the ultrasonic pulse velocity and the core strength. Also, this paper recommend the relationships as the aging and as the element.

• Corrosion Science and Technology
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• 제7권2호
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• pp.125-129
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• 2008

Results of corrosion testing for different grades of titanium, copper, zinc, alluminium alloys and steels after two years of outdoor exposure under humid tropical urban and marine conditions have been presented and discussed. Mass loss and corrosion product characteristics for the exposed specimens at Hanoi testing site with high humidity and Nhatrang marine stations (at 100 and 1,000 meters distances from sea) with different airborne salinities (35.9 and $90.0mg/m^2.d$ respectively) have been selected for investigation. From time dependence of the specimen mass loss and corrosion product characteristics, the strong influence of environmental parameters upon durability for the investigated metals and alloys has been demonstrated. Only titanium alloys show high resistance to the marine conditions. All the other specimens (copper, zinc, alluminium alloys and steels) have been underwent strong deterioration under influence of aerosol salinity. Results of corrosion products analysis have been also presented for characterization of environmental impact on the metal degradation processes.

• 비파괴검사학회지
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• 제29권6호
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• pp.534-549
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• 2009

As the thin film technology has emerged in various fields, adhesion of the film interface becomes an important issue in terms of the longevity and durability of thin film devices. Diverse nondestructive methods utilizing acoustic techniques have been developed to assess the interfacial integrity. As an effective technique based on the ultrasonic wave focusing and the surface acoustic wave(SAW) generation, scanning acoustic microscopy(SAM) has been investigated for adhesion evaluation. Visualization of film microstructures and quantification of adhesion weakness levels by SAW dispersion are the recent achievements of SAM. To overcome the limitations in the theoretical dispersion model only suitable for perfectly elastic and isotropic materials, a new model has been more recently developed in consideration of film anisotropy and viscoelasticity and applied to the adhesion evaluation of polymeric films fabricated on semiconductive wafers.

• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2001년도 정기학술대회
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• pp.91-97
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• 2001

These Study are for the development of the reliability assessment test code and test equipment and test procedures of the heavy sluice gate hydraulic cylinder. Because there is no reliability test code for the heavy sluice gate hydraulic cylinder inside and outside of the country, the modified reliability test code is made reference for the related existing standards like as ISO, JIS, MIL, TUV, DIN, KS and etc. In this study, the novel method is proposed to evaluate efficiency of the heavy sluice gate hydraulic cylinder on the loading conditions and established the conditions of the acceleration life test to reduce the testing time and cycles. The testing equipments for life test, lode operating test, high and low temperature test and salt spray test have been established for 8 month, and the reliability tests are accomplished. The test results of the heavy sluice gate hydraulic cylinder which is produced and tested initially in Korea are satisfied the durability life cycle on the using conditions.

• Toxicological Research
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• 제22권3호
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• pp.237-244
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• 2006

Two kinds of sepiolite, a $500^{\circ}C$ heat-treated sepiolite, and a $700^{\circ}C$ heat-treated sepiolite were analyzed for their physicochemical properties. After these sepiolites were instilled into rat lungs, the effects of the substances on lung pathological changes were evaluated. The lungs instilled with sepiolite increased their weight compared with the unexposed control. The pathological examination further showed increased legions of granuloma with early fibrosis. The heat treated sepiolites, however, did not show any toxicological differences from the untreated sepiolites. Thus chronic experiments are needed to evaluate the durability of mineral fibers, which is an essential experiment for evaluating biopersistence of fibers in lungs.