• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 추계 학술논문 발표대회
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• pp.45-46
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• 2017

As the environment and energy problems such as global climate change (global warming, urban heat island phenomenon) and energy depletion have come to the fore, the construction and waterproofing industry are responding more critically to the demands of global green technology and are employing more eco-friendly technologies as of recent. In this study, the application of the waterproofing material with thermal response performance in construction buildings was investigated to confirm whether the thermal performance is being properly secured by the change of the surface temperature. Experimental results showed that the surface temperature difference between before and after the application is at least 19.8℃ at the maximum 26.3℃. When the degradation rate is converted, the degradation effect of about 40% on average was confirmed.

• 한국건축시공학회지
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• 제18권6호
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• pp.559-567
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• 2018

외단열 마감 공법에서 사용되는 바탕조정재는 화재가 발생하는 경우 얇은 마감과 폴리머의 연소로 인해 표면부가 급속하게 붕괴되어 화재에 취약한 소재이다. 본 연구에서는 열적 성능이 우수한 팽창 흑연을 사용할 경우 바탕조정재의 성능을 개선할 수 있을 것으로 기대하였다. 실험결과, 팽창흑연을 사용한 바탕조정재는 부착강도 저하 및 물흡수계수 등의 감소가 발생하는 문제점이 있으나 플라이애시와 실리카흄을 사용하여 물리적 성능이 향상되는 것으로 나타났다. 팽창흑연을 사용한 바탕조정재는 복합 단열 시험체 표면의 페놀폼은 화염에 의한 표면 뚫림이 나타나지 않아 열원의 투과를 감소시킬 수 있을 것으로 나타났다.

• 품질경영학회지
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• 제25권2호
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• pp.102-111
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• 1997

In this paper I discuss a method of constructing the confidence region for the logistic response surface model. The construction involves a, pp.ication of a general fitting procedure because the log odds is linear in its parameters. Estimation of parameters of the logistic response surface model can be accomplished by maximum likelihood, although this requires iterative computational method. Using the asymptotic results, asymptotic covariance of the estimators can be obtained. This can be used in the construction of confidence regions for the parameters and for the logistic response surface model.

• 한국CDE학회논문집
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• 제3권2호
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• pp.87-102
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• 1998

Given a sequence of cross-sectional curves, the skinning method generates a freeform surface that interpolates the given curves in that sequence. This thesis presents a construction method of a B-spline skinning surface that is fair and satisfies volume constraints. The fairness metric is based on the parametric energy functional of a surface. The degrees of freedom in surface control are closely related lo control points in the skinning direction. The algorithm fur finding a skinning surface consists of two step. In the first step, an initial fair surface is generated without volume constraints and one coordinate of each control point is fixed. In the second step, a final surface that meets all constraints is constucted by rearranging the other coordinates of each control point that defines the initial surface A variational Lagrange optimization method produces a system of nonlinear equations, which can be solved numerically. Moreover, the reparametrization of given sectional curves is important for the construction of a reasonable skinning surface. This thesis also presents an intuitive metric for reparametrization and gives some examples that are optimized with respect to that metric.

• 한국건축시공학회지
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• 제7권4호
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• pp.125-132
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• 2007

The use of Self-Leveling material is increasing recently. This paper assesses the quality of surface layer of concrete floor when Self-Leveling material is defective. The paper shows how to predict the defect of SL material before construction begins. The relationship between the quality of surface layer of concrete floor and the defect of SL material was determined and the quality of surface layer of concrete floor was then estimated. The relations between the quality of surface layer and the defect of SL material were determine considering surface strength, moisture, and consistency of surface layer. Absorbing amount was used as the indicator of consistency and the absorbing amount of test material was measured. Then the relations between the test material and surface strength were determined. Generally concrete floor with greater consistency has greater surface strength, however in this study, we hound that high impact concrete floor could have lower surface strength as the consistency gets bigger. The relations between the level of defect occurred in SL material and the quality of surface layer were examined and we clarified that the surface layer with lower consistency gets higher possibility to occur exfoliation in early stage, one or two weeks after constructing SL material. When the consistency is sufficient, the occurring situation of defect depends upon the moisture of surface layer. Little amount of moisture gets higher possibility not to occur the defect. As the amount increases, fissure generates and early exfoliation may occur. In addition, the level of fissure is highly related with the surface strength.

• 소성∙가공
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• 제12권4호
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• pp.348-357
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• 2003

In order to construct the extrusion die surface of arbitrarily shaped sections, an automatic surface construction method based on NURBS surface and area mapping method is proposed in the present work. A center point fur area mapping is determined by introducing the mapping concept based on constant area proportionality between original billet and final product. The characteristic points of inlet profile are determined using the traditional area mapping method and the root finding numerical method. The inlet and outlet profiles are precisely described with NURBS curves using the characteristic points of entry and exit sections. For the construction of NURBS surface, an interpolation method for the pre-determined two section curves has been developed to be used in the generation of interior control points and weights. To show the validity of the proposed method, automatic die surface generation is carried out for the several kinds of shaped sections.

• 콘크리트학회논문집
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• 제19권5호
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• pp.595-602
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• 2007

최근 CFRP (탄소섬유보강폴리머) 보강재를 이용한 콘크리트 구조물 보강이 교량 및 건축물 등에 널리 사용되고 있다. 본 연구에서는 교각 두부 보강에 프리스트레스가 도입된 표면매립 CFRP를 적용하였다. 적용된 공법의 효율성을 검증하기 위해 7개의 실험체를 제작하였으며, 기준 실험체, 외부 강선 보강 실험체, 탄소판 보강 실험체, 탄소 바 보강 실험체로 구성되어 있다. 보강재의 종류, 프리스트레스력의 크기를 실험 변수로 두어 실험을 하였으며, 실험 결과 프리스트레스가 도입된 표면매립 CFRP 보강 실험체의 극한강도가 기준 실험체에 비해 약 $20{\sim}33%$ 증가하는 것으로 나타났다. 또한 동일한 프리스트레스 도입량을 갖는 프리스트레스가 도입된 표면매립 CFRP 보강 실험체와 외부강선보강 실험체는 극한하중이 유사한 것으로 나타났다.

• 한국터널지하공간학회 논문집
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• 제17권2호
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• pp.175-187
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• 2015

본 논문은 저심도 철도 건설을 위해 사용될 트렌치 쉴드 장비의 설계에 대한 내용을 다루고 있다. 저심도 철도는 도로 아래의 5~7 m에 설치되며 개착 공법으로 시공을 하게 된다. 개착 공법으로는 주로 가시설을 이용한 공법이 많이 이용하고 있는데, 현 기술 수준으로 가시설을 이용한 공법의 한계점으로 높은 시공비와 시공 기간을 들 수 있다. 이러한 단점을 극복하기 위한 트렌치 쉴드 장비의 개발이 진행되고 있다. 트렌치 쉴드 장비는 주변 토압을 지지하는 토류판과 하단부의 굴착기로 구성되어 있는데, 토류판이 가시설의 역할을 대신하며 전면 하단에 굴착기가 부착되어 굴착시간을 단축 시켜준다. 또한 굴착 후 바로 세그먼트를 삽입을 하기 때문에 시공시간을 상당히 절약할 수 있다. 본 논문에서는 트렌치 쉴드 장비의 주요 기능을 담당하는 굴착기의 비트 설계 및 요구되는 모터 동력의 산정에 대한 연구 내용을 서술하였다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.113-120
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• 2001

A frame slab method has been proved as a possible and profitable construction solution for the urban tunnels with very shallow overburden and the excavation from the surface Is strictly limited. Since this method allows only a small amount of construction activities in the ground surface, the disturbances to the public and the surface traffic can be drastically reduced compared with the ordinary cut-and-cover method. The construction sequences of the method and the some of critical cautions needed are described in detail. Also a comprehensive numerical analysis including 2-D and 3-D analysis have been performed to verify the stability of the ground during the construction. It is revealed from this study that the frame slab method can be a quite successful solution for the shallow overburden tunnelling in urban area.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 추계 학술논문 발표대회
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• pp.101-104
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• 2007

Currently most of underground structures in domestic apartment projects are being designed for parking lot and essential parking area is growing due to the increase in car-holding number per household. Moreover, most underground parking lots of today are combined with basement, therefore a pleasant environment in underground space is strongly needed for the dwellers' use. However, there always occur high percentage of humidity and surface condensation in underground parking lot because of the nature of underground structure and they are having a bad influence on the comfort and health of dwellers. Therfore, this study is planned to compare and examine the porformance and properties of currently used construction methods to prevent condensation and finally present the most suitable method.