• 한국건설관리학회논문집
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• 제17권2호
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• pp.135-145
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• 2016

최근 국내 공동주택 골조공사에 있어서 소음저감형 알루미늄 거푸집의 활용이 증가하고 있다. 그러나 현재까지 개발된 소음저감형 알루미늄 거푸집은 복잡한 작업프로세스로 인해 작업 생산성이 저하되고, 특히 설치 해체 작업 시 알루미늄의 물성으로 인해 발생하는 소음을 여전히 방지하지 못한다는 문제점을 지니고 있다. 따라서 본 연구의 목적은 새로운 소음저감형 알루미늄 거푸집의 최적 개념디자인을 제안하고, 최적 개념디자인을 토대로 제작된 워킹목업(Working Mock-up)의 기술적 타당성을 검토하는 것이다. 이를 위해 본 연구에서는 기존 알루미늄 거푸집의 분석을 통해 새로운 형태의 소음저감형 알루미늄 거푸집 개넘디자인 3개 안을 도출하였으며, 현장 전문가 설문조사를 통해 AHP 분석을 수행하였다. AHP 분석 기법을 활용하여 Trade-off Analysis를 수행한 결과, 안전성(0.52)과 작업편의성(0.54) 부분에서 가장 높은 가중치 값이 도출된 '드롭다운 동바리와 가변빔이 적용된 소음저감형 시스템 알루미늄 거푸집'이 최적 개념디자인으로 선정되었다. 본 연구를 통해 도출된 소음저감형 알루미늄 시스템 거푸집의 최적 개념디자인은 기존 소음저감형 시스템 거푸집의 문제점을 해결하고, 실질적인 소음저감은 물론 작업 편의성 및 노무자의 안전성이 제고된 실제 소음저감형 알루미늄 거푸집의 개발에 활용될 수 있을 것으로 기대된다.

• Nuclear Engineering and Technology
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• 제45권3호
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• pp.295-310
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• 2013

Industry- or regulatory-sponsored research activities on the resolution of Generic Safety Issue (GSI)-191 were reviewed, especially on the chemical effects. Potential chemical effects on the head loss across the debris-loaded sump strainer under a post-accident condition were experimentally evidenced by small-scale bench tests, integrated chemical effects test (ICET), and vertical loop head loss tests. Three main chemical precipitates were identified by WCAP-16530-NP: calcium phosphate, aluminum oxyhydroxide, and sodium aluminum silicate. The former two precipitates were also identified as major chemical precipitates by the ICETs. The assumption that all released calcium would form precipitates is reasonable. CalSil insulation needs to be minimized especially in a plant using trisodium phosphate buffer. The assumption that all released aluminum would form precipitates appears highly conservative because ICETs and other studies suggest substantial solubility of aluminum at high temperature and inhibition of aluminum corrosion by silicate or phosphate. The industry-proposed chemical surrogates are quite effective in increasing the head loss across the debris-loaded bed and more effective than the prototypical aluminum hydroxide precipitates generated by in-situ aluminum corrosion. There appears to be some unresolved potential issues related to GSI-191 chemical effects as identified in NUREG/CR-6988. The United States Nuclear Regulatory Commission, however, concluded that the implications of these issues are either not generically significant or are appropriately addressed, although several issues associated with downstream in-vessel effects remain.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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• pp.8-9
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• 2019

Euro forms and aluminum forms, which are currently used in formwork construction sites are limited by their heavy weight and the use of environmentally hazardous form oils. Therefore, in this study, 'eco-friendly light weight form' was developed, which does not require form oils during the removal process of form. In addition, the superiority of the developed form was verified by comparison with Euro forms and aluminum forms in terms of noise generation and weight. Application of the eco-friendly light weight form in construction sites is expected to reduce the noise level, and increase workers' convenience. The productivity of formwork is also increased.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.969-972
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• 2008

본 연구는 온도변화에 따라 기초영향인자가 콘크리트와 알루미늄 거푸집간의 표면 마감성에 미치는 영향에 대하여 분석한 것으로 그 결과를 요약하면 다음과 같다. 육안관찰상 코팅합판과 무손상 알루미늄 거푸집의 경우 비슷한 결과를 나타냈으며, 온도변화에 따라서는 알루미늄 거푸집을 사용한 경우 온도가 높아질수록 표면품질이 약간씩 저하하는 것을 확인할 수 있었다. 표면조도의 경우 온도변화에 따른 차이는 거의 나타나지 않았으며, 박리제의 도포여부에 따른 차이가 발생하였다. 온도변화에 따른 표면공극분포는 온도가 증가할수록 $0.1{\sim}1mm$ 범위의 미세한 기포가 증가하여 화학반응이 촉진됨을 확인할 수 있었으며, 다른 범위의 공극도 증가하였다. 또한, 온도가 증가할수록 다른 인자들의 영향이 더욱 커지는 것을 확인할 수 있어 온도증가에 의해 알루미늄 거푸집을 이용하는 콘크리트의 표면품질이 저하함을 확인할 수 있었다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권1호
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• pp.1-8
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• 1998

Biomass of non-living brown seaweed Sargassum fluitans pretreated by different methods is capable of taking up more than $10\%$ (11 meq/g) of its dry weight in aluminum at a pH of 4.5. It is indicated that the biomass sequestered the aluminum in the form of polynuclear aluminum species. The fraction of $Al(OH)_3$ Precipitated in the aluminum nitrate solution without biomass at pH 4.5 increased as the Al concentration increased. Aluminum-alginate complex precipitated in the solution as alginate was partially released from the biomass. External colloidal precipitate occurring in native and protonated S. fluitans biomass sorption systems caused a significant difference in Al sorption isotherms determined by standard and desorption methods, respectively, Sodium ions added for pH adjustment were not sorbed at all in the presence of aluminum ions.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2019년도 추계 학술논문 발표대회
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• pp.10-11
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• 2019

The purpose of this study is to validate the environmental performance of the 'eco-friendly lightweight form' in the construction process. Unlike existing euro form and aluminum form, the proposed form does not require form oil during the process of concrete casting and is lightweight because it is made of engineering plastic. Therefore, eco-friendly lightweight form will reduce the $CO_2$ emissions in the construction process. To verify the hypothesis, the study compared existing forms and eco-friendly light weight form's $CO_2$ emissions in each stage in construction process when using 1,000 forms and 100 times from the LCI(Life Cycle Inventory) data. The total $CO_2$ emissions of the eco-friendly light weight form were 30,487kg $CO_2$, which equated to about 58% and 20% less emissions than the euroform and aluminum form. The result of the study verified that the eco-friendly lightweight form was effectively reduced $CO_2$ emission in the construction process.

• International Journal of Automotive Technology
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• 제4권3호
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• pp.141-147
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• 2003

For improving high-safety, convenience, and ride comfort, the automotive design suffers from radical increase of the weight, the recycling-related rules, regulations on the waste gas, and environmental protection of the resources. Among them, it is well known that the weight increase is the most critical. Thus, in order to minimize the weight of the body-in-white that takes up 20-30% of the whole weight of the automobile, most automotive manufacturers have attempted to develop the aluminum intensive body-in-white using aluminum space frames. In this research, the crush test and simulation for aluminum extrusions are performed to evaluate the collapse characteristics of that light weighted material. Also. the same test and simulation was done for aluminum extrusions filled with structural foam. Then, these results are analyzed and compared. From these studies, the effectiveness of structural foam is evaluated in improving automotive crashworthiness. Finally, the design strategy and guideline of the structural form are suggested in order to improve the crashworthiness for aluminum space frame in the vehicle.

• 한국해양공학회지
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• 제26권6호
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• pp.14-18
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• 2012

A 30ft class aluminum leisure boat is newly developed and the resistance performances are investigated by a model test at a high-speed circulating water channel. The effect of a fin attached to the side of the hull is studied at two different displacements. Wave patterns are observed to make clear the relationship between the resistance performance and wave characteristics. It can be found that a chine position at the draft line can have a strong effect on the resistance performance around a certain velocity range.

• 대한기계학회논문집A
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• 제33권2호
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• pp.108-113
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• 2009

The mixing of two dissimilar aluminum alloys in friction stir welding (FSW) was investigated using etching. The results show that the materials from the retreating side mixed into the advancing side in rather narrow and elongated bands whereas the materials from the advancing side mixed into the retreating side in the form of thick bands and lobes. A computational method using smoothed particle hydrodynamics (SPH) is introduced as a way to properly describe the complex mixing behavior in FSW.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1216-1218
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• 1997

Hydrolysis of BTDA-ODA: MPDA, PMDA-ODA, PIQ polyimides were investigated by FT-IR. The results showed that hydrolysis depends on structure of polyimide and that polyimide obtains hydrolytic stability by curing. Polyimide-aluminum interfaces were characterized by RAIR. It was concluded that imidization of the polyamic acid to polyimde was inhibited by interaction of acid groups with substrate to form aluminum carboxylate.