• 한국도로학회논문집
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• 제15권1호
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• pp.1-9
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• 2013

PURPOSES: The purpose of this study is to evaluate physical properties, durability, fatigue resistance, and long-term performance of poly-urethane concrete (PU) which can be possible application of thin layer on long-span orthotropic steel bridge and to check structural stability of bridge structure. METHODS : Various tests of physical properties, such as flexural strength, tensile strength, bond strength and coefficient of thermal expansion tests were conducted for physical property evaluation using two types of poly urethane concrete which have different curing time. Freezing and thawing test, accelerated weathering test and chloride ion penetration test were performed to evaluate the effect of exposed to marine environment. Beam fatigue test and small scale accelerated pavement test were performed to assess the resistance of PU against fatigue damage and long-term performance. Structural analysis were conducted to figure out structural stability of bridge structure and thin bridge deck pavement system. RESULTS: The property tests results showed that similar results were observed overall however the flexural strength of PUa was higher than those of PUb. It was also found that PU materials showed durability at marine environment. Beam fatigue test results showed that the resistances of the PUa against fatigue damage were two times higher than those of the PUb. It was found form small scale accelerated pavement test to evaluate long-term performance that there is no distress observed after 800,000 load applications. Structural analysis to figure out structural stability of bridge structure and thin bridge deck pavement system indicated that bridge structures were needed to increase thickness of steel deck plate or to improve longitudinal rib shape. CONCLUSIONS: It has been known that the use of PU can be positively considered to thin layer on long-span orthotropic steel bridge in terms of properties considered marine environment, resistance of fatigue damage and long-term performance.

• Journal of the Korean Wood Science and Technology
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• 제36권4호
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• pp.58-65
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• 2008

집성재의 구조부재로서의 이용에 있어서는 접합철물(connector)과 파스너(fastener)에 의한 접합이 대부분을 차지하고 있다. 이들 접합부의 역학적 거동은 파스너의 지압과 부재의 전단현상으로 설명할 수 있다. 집성재 내의 층재 구성상태에 따른 전단성능, 2면전단 핀접합부의 인발에 의한 전단성능, 실대 기둥-보 2면전단 핀접합부의 모멘트 저항성능을 검토하였다. 집성접착된 부위의 경우, 두 층재간의 보완작용에 의해 밀도 및 전단강도에 있어서도 적층효과를 발휘하였다. 소시험편의 전단강도를 이용한 핀접합부의 2면전단강도와 모멘트 저항성능을 예측할 경우 다소의 보정이 필요할 것으로 판단되었다. 기둥-보 접합부의 모멘트저항성능 예측은 소시험편 전단강도의 10%를 저감하여 이용하면 안전하게 예측가능한 것으로 판명되었다.

• 방사선산업학회지
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• 제7권1호
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• pp.45-49
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• 2013

In tissue engineering application, a fibrous structure of scaffolds has been issued as an alternative system to regulate cell survival and tissue regeneration, and electrospinning technique has been popularly used to generate fibrous meshes or sheets mimicking the structure of native extracellular matrix (ECM). However, recent strategy in the scaffold development is expanded to provide the structural property as well as a biological property of native ECM, a variety of surface modification techniques have been used to introduce biological property. In this study, we developed biomimetic poly(L-lactide-co-${\varepsilon}$-caprolactone) (PLCL) nano- and micro-fibrous scaffolds as a unique platform with structural and biological properties with native ECM using electrospinning method and gamma-ray irradiation. Surface morphology of the scaffolds was observed by scanning electron microscopy, and alteration of surface property was evaluated with toluidine blue O staining, water contact angle measurement and ATR-FTIR analysis.

• The Journal of Asian Finance, Economics and Business
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• 제4권3호
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• pp.57-73
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• 2017

In the current competitive marketplace of real estate business, tenant satisfaction measurement is one of the important indicators to monitor competitiveness in industrial property development. It has become an industry standard to measure tenant satisfaction, commonly called customer satisfaction. Customer satisfaction has become the widely used metric to manage customer loyalty (Keiningham, Gupta, Aksoy, & Buoye, 2014). The aim of this research is to determine the impact of property management services on tenants' satisfaction with the three identified variables i.e. facility management, perceived quality and lease management. Structural equation modeling (SEM) is applied to build constructs and test the hypotheses with the collected survey samples. Of the three variables, facility management is the most influential factor that leads to tenant satisfaction with industrial buildings. Next, perceived quality is another important factor that contributes to tenants' pleasure. Compared with these two, lease management fares worse, having the least extensive effect on tenant satisfaction, and could be disregarded. The ultimate impact of tenant satisfaction is about tenant retention and recommendation. The overall findings of this research will potentially help real estate developers to develop a better property management system, leasing program and tenant retention strategy.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.82-82
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• 2008

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1988년도 가을 학술발표회 논문집
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• pp.30-35
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• 1988

An analytical study was conducted using the Galerkin technique to determine the behaviour of thin fibre-reinforced and laminated composite pipes under soil pressure. Geometric nonlinearity and material linearity have been assumed. We assumed that vertical and lateral soil pressure are proportional to the depth and lateral displacement of the pipe respectively. And we also assumed that radial shear stress is negligible because the ratio of the thickness to the radius of pipe is very small. We, in this paper, discuss the effect of the number of layer, fiber orientation, and soil property.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1998년도 봄 학술발표회 논문집
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• pp.398-405
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• 1998

This study investigated to the stability of open car parks below $600^{\circ}C$, as to predict behavior of bare FR steel structure noosed to fire. Especially, This study evaluated deformation of steel structure members of open car parks, considering change of material property by temperature. From the numerical analysis, we know the fact that the deformations comparing of standard values are stable to use the FR steel below 600 $^{\circ}C$ in open car parks plan

• 건축역사연구
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• 제2권2호
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• pp.9-25
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• 1993

The storehouse for ice was an installation to use the ice during summer season. Even though it shows various versions of styles according to the different periods and regions, it consistently developed through the history with structural characteristics. In this study, first, the management of the icehouse system through the history is examined; second, seven existing icehouses in Korea are investigated in terms of their size, material, history, structure ; and finally, the structural patterns of the ice houses are examined.

• 전산구조공학
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• 제7권3호
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• pp.167-176
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• 1994

균열전파 현상은 항상 형상이 변화하는 대표적인 문제중의 하나이다. 본 연구는 준-정적 균열전파 현상을 해석하기 위하여 들로네이 특성을 이용한 국지 요소재편 알고리즘을 제시하였다. 이 알고리즘은 요소 재편성과 세분화를 모두 수행할 수 있도록 준비되었다. 적용예로 M 적분법을 사용하여 주로 혼합 모우드로 균열이 전파되는 스폴링 현상을 해석하였다.

• 대한수학회지
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• 제53권2호
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• pp.415-431
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• 2016

This note is concerned with examining nilradicals and Jacobson radicals of polynomial rings when related factor rings are Armendariz. Especially we elaborate upon a well-known structural property of Armendariz rings, bringing into focus the Armendariz property of factor rings by Jacobson radicals. We show that J(R[x]) = J(R)[x] if and only if J(R) is nil when a given ring R is Armendariz, where J(A) means the Jacobson radical of a ring A. A ring will be called feckly Armendariz if the factor ring by the Jacobson radical is an Armendariz ring. It is shown that the polynomial ring over an Armendariz ring is feckly Armendariz, in spite of Armendariz rings being not feckly Armendariz in general. It is also shown that the feckly Armendariz property does not go up to polynomial rings.