• 한국터널지하공간학회 논문집
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• 제14권2호
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• pp.131-139
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• 2012

본 연구에서는 도심지 소구경 터널굴착공법에서 파형강판으로 제작된 liner plate의 거동특성에 대해 알아보기 위해 유한요소 해석 프로그램인 MIDAS/GTS를 이용하여 수치해석을 실시하였다. 토피고 변화에 따라 liner plate의 거동특성을 알아보기 위해 토피고는 5 m, 10 m, 15 m, 20 m, 25 m 5가지 각 조건으로 해석을 실시하였다. 수치해석결과 liner plate의 최대변위와 최대축응력은 부재의 하단부에서 발생되며, 최대전단응력의 경우 부재의 천단부에서 발생되는 것으로 확인되었다. 또한 토피고에 따른 liner plate의 변위, 응력, 전단응력의 변화는 있었으나 그 차이가 미미하고 토피고가 증가함에 따라 점점 구조적 안정성이 확보되는 것으로 판단된다.

• 한국압력기기공학회 논문집
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• 제16권1호
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• pp.37-41
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• 2020

The Nuclear containment building is a main safety-related structure that performs shielding and conservation functions to prevent highly radioactive materials from leakage to the outside environment in the case of various environmental conditions and postulated accidents. The containment building contains a reactor, steam generator, pressurizer, tank, reactor coolant system, auxiliary system and engineering safety system, and is designed so that highly radioactive materials above the limits specified in 10 CFR 100 do not escape to the outside environment in the case of LOCA(Loss of Coolant Accident) for instance. The containment metal liner plate(CLP) is a carbon steel plate with a nominal plate thickness of 6 mm, which functions as a mold for the wall and dome of the containment building when concrete is filled, fulfills airtightness to prevent leakage of seriously radioactive materials. In recent years, backside corrosion was found on the liner plate in some domestic nuclear power plants. The main cause of backside corrosion was unfilled concrete. In this paper, an inspection technique of assessing filling suitability for CLP backside concrete is developed. Results show that the validity of inspection technique for CLP backside concrete using vibration sensor is successfully verified.

• 한국압력기기공학회 논문집
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• 제15권1호
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• pp.46-52
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• 2019

This work proposes a noncontact ultrasonic transducer for detecting wall-thinning of containment liner plates of nuclear power plants by measuring their thickness without physical contact. Because the containment liner plate is designed to prevent atmospheric leakage of radioactive substances under severe nuclear accident, its wall-thinning inspection is important for safety of nuclear power plants. Wall-thinning investigation of containment liner plates have been carried out by measuring their thickness with contact-type ultrasonic thickness gauge by inspectors and needs a lot of time and cost. As an alternative, an electromagnetic acoustic transducer measuring precisely thickness of containment liner plates without any physical contact or couplant was suggested in this research. A transducer generating and measuring shear ultrasonic waves in thickness direction was designed and wave field produced by the transducer was analyzed to verify the design. The working performance of the suggested transducer was tested with carbon steel plate specimens with various thicknesses. The test result shows that the proposed transducer can measure thickness of the specimens precisely without any couplant and implies that swift scanning of wall-thinning of containment liner plates will be possible with the proposed transducer.

• 펄프종이기술
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• 제36권2호
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• pp.17-23
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• 2004

The effects of refining consistency and plate gap on the specific energy consumption and physical properties of liner were investigated. Higher refining consistency and narrower plate gap brought about the reduction of specific energy consumption to decrease the freeness. Refining consistency and plate gap did not affect the bulk, Taber stiffness and compression index. The reduction of freeness and/or the increase of specific energy consumption caused the decrease of bulk and Taber stiffness, but increased the compression index. The effect of grammage on bulk was not observed, but Taber stiffness and compression index were increased with grammage. The bulk was decreased with the reduction of freeness rapidly at the above 400 mL CSF, and then levelled off. It is expected that the reduction of energy consumption could be obtained from the application of higher refining consistency and narrower plate gap during refining.

• 대한치과보철학회지
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• 제41권6호
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• pp.732-746
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• 2003

Statement of problem. Soft lining materials, also referred to as tissue conditioning materials, tissue heating materials, relining materials, soft liners or tissue conditioners, were first introduced to dentistry by a plastic manufacturer in 1959. Since the introduction of the materials to the dental field, their material properties have been continually improved through the effort of many researchers. Soft lining materials have become widely accepted, particularly by prosthodontists, because of their numerous clinical advantages and ease of manipulation. Unfortunately, few reports have been issued upon the topic of increasing the bond strength between the base metal alloy used in cast denture bases and PMMA soft liner modified with 4-META, nor upon the pattern of debonding and material change in wet environment like a intra oral situation. Purpose. The purposes of this study were comparing the bond strength between base metal alloy used for the cast denture bases and PMMA soft liner modified with 4-META, and describing the pattern of debonding and material property change in wet environment like the intraoral situation. Material and Methods. This study consisted of four experiments: 1. The in vitro measurement of shear bond strength of the adhesive soft liner. 2. The in vitro measurement of shear bond strength of the adhesive soft liner after 2 weeks of aging. 3. A comparison of debonding patterns. 4. An evaluation the Relation time of modified soft liner. The soft liner used in this study was commercially available as Coe-soft (GC America.IL.,USA), which is provided in forms of powder and liquid. This is a PMMA soft liner commonly used in dental clinics. The metal primer used in this study was 4-META containing primer packed in Meta fast denture base resin (Sun Medical Co., Osaka, Japan). The specimens were formed in a single lap joint desist which is useful for evaluating the apparent shear bond strength of adhesively bonded metal plate by tensile loading. Using the $20{\times}20mm$ transparent grid, percent area of adhesive soft liner remaining on the shear area was calculated to classify the debonding patterns. To evaluate the change of the initial flow of the modified adhesive soft liner, the gelation time was measured with an oscillating rheometer (Haake RS150W/ TC50, Haake Co., Germany). It was a stress control and parallel plate type with the diameter of 35mm. Conclusion. Within the conditions and limitations of this study, the following conclusions were drawn as follows. 1. There was significant increase of bond strength in the 5% 4-META, 10% 4-META containing groups and in the primer coated groups versus the control group(P<0.05). 2. After 2 weeks of aging, no significant increase in bond strength was found except for the group containing 10% 4-META (P<0.05). 3. The gelation times of the modified soft liner were 9.3 minutes for the 5% 4-META containing liner and 11.5 minutes for the 10% 4-META liner. 4. The debonding patterns of the 4-META containing group after 2 weeks of aging were similar to those of immediaely after preparation, but the debonding pattern of the primer group showed more adhesive failure after 2 weeks of aging.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1221-1229
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• 2022

In this work, the guided wave de-bonding area-detecting technique was studied for application to containment liner plates in nuclear power plant areas. To apply this technique, an appropriate Lamb wave mode, symmetric and longitudinal dominance, was verified by the frequency shifting technique. The S0 2.7 MHz mm Lamb wave mode was chosen to realize quantitative experimental results and their visualization. Results of the bulk wave, longitudinal wave mode, and comparison experiments indicate that the wave mode was able to distinguish between the de-bonded and bonded areas. Similar to the bulk wave cases, the bonded region could be distinguished from the de-bonded region using the Lamb wave approach. The Lamb wave technique results showed significant correlation to the de-bonding area. As the de-bonding area increased, the Lamb wave energy attenuation effect decreased, which was a prominent factor in the realization of quantitative tomographic visualization. The feasibility of tomographic visualization was studied via the application of Lamb waves. The reconstruction algorithm for the probabilistic inspection of damage (RAPID) technique was applied to the containment liner plate to verify and visualize the de-bonding condition. The results obtained using the tomography image indicated that the Lamb wave-based RAPID algorithm was capable of delineating debonding areas.

• 대한치과보철학회지
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• 제40권3호
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• pp.269-274
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• 2002

statement of problem The viscoelastic property is the most important and peculiar characteristics of soft liners. But the authorized standard is not certainly established than other dental materials. purpose of study This study is aimed to compare the initial flow of gelation of the modified soft liner with 4-META with that of PMMA soft liners using dynamic method and evaluate the clinical acceptance of the trial materials. materials and method This study consists of 3 groups with the given % of 4-META powder in the Coe soft liquid; 0%, 5%, 10% Each group was tested for 10 times to record the change of G′values during 3 hours. the gelation time was recorded by the oscillating rheometer with parallel plate with 1 rad/sec. results As the results of this study, the gelation time of modified soft liner was elongated by 5 to 6 minutes. conclusion The mean gelation time of modified soft liner could be within the range of clinically acceptable.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.195-195
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• 2015

반도체 제조 시 ohmic contact을 형성하고, barrier metal layer형성을 위해 NH3 기체를 사용하는 rapid thermal nitridation (RTN)은 반도체 공정에 있어 매우 중요한 핵심 기술이다. 그러나 공정 진행 시 발생하는 공정 부산물에 의한 chamber오염으로 인해 매우 정확히 입사 되어야 할 thermal energy의 controllability가 저하되고 있어, 미세 공정능력 구현의 한계에 부닥치고 있다. 본 연구에서는 quartz plate liner를 적용하여 RTN 공정에서 발생하는 공정 부산물인 ammonium chloride (NH4Cl)의 chamber 표면 증착을 최소화하였고, 공정 진행 온도의 controllability를 확보하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2011년도 정기 학술대회
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• pp.336-339
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• 2011

본 논문에서는 유한요소 프로그램 (ANSYS)을 이용하여 돔격납철판 (dome containment liner plate)의 양중시 좌굴특성의 연구를 수행하였다. 원전 격납철판의 양중시, 양중 와이어(wire)의 구조적인 배치특성상 격납철판에 압축력이 유발되고, 이러한 압축력은 격납철판의 좌굴을 일으킬 수 있다. 다양한 양중인자 (lifting factors)를 고려한 격납철판 유한요소모델을 수립하고, 이러한 양중인자들의 좌굴특성에 미치는 영향을 고찰하였다. 양중 와이어의 체결위치의 높이가 낮을 수록 좌굴강도가 증가하며, 라이너 플레이트 두께에 비례하여 좌굴강도가 증가하였다.

• 기계와재료
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• 제22권1호
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• pp.76-83
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• 2010

원자력발전소의 구조건전성 및 안전성을 확보하는데 있어서 격납건물의 중요한 목적은 방사성물질의 유출을 방지하는 최후의 보루 역할을 한다는 것이다. 또한 원전의 격납건물 선설에 있어서 고려해야 될 가장 중요한 인자는 안전성과 경제성이다. 이러한 목표를 달성하기 위해, 최근 국내에서 첨단 CLP(Containment Liner Plate) 공법이 개발되어 신월성 원전 2호기에 적용되었다. 이 공법은 기존의 CLP 2단 모듈화 공법에서 한 단계 발전한 CLP 3단 모듈화 공법으로 건설기간 단축, 비용 절감 및 구조건전성을 확보하는 계기가 되었다. 그리고 이러한 공법을 바탕으로 국내건설 뿐만 아니라 원전 수출에 커다란 기여를 하게 되었다. 이 글에서는 국내 원자력발전소 CLP 설치에 있어서, 기존의 방법과 새로운 공법에 대한 비교/분석, 공정, 장/단점 등을 연구, 조사해 보았다.