• 한국보육지원학회지
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• 제12권4호
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• pp.1-21
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• 2016

The current study examined the effects of early social support of first-time mothers on the home environment for their preschool-aged children via the mediation of mothers' depression. The study sample included 755 first-time mothers participating in the Panel Study on Korean Children(PSKC). Using Structural Equation Modeling(SEM), the longitudinal structure from mothers' social support when the child is one year old to the quality of the home environment when the child is 4 years old was examined. The results revealed that mothers' social support at age 1 predicted social support at age 3, which in turn predicted higher quality of the home environment for their children at age 4. The mediation of depression was also significant. Mothers' social support predicted lower levels of depression at both phases and mothers' depression was significantly associated with the quality of the home environment.

• Earthquakes and Structures
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• 제15권1호
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• pp.97-111
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• 2018

Buildings featuring a transfer structure can be commonly found in metropolitan cities situated in regions of lower seismicity. A transfer structure can be in the form of a rigid plate or an array of deep girders positioned at the podium level of the building to support the tower structure of the building. The anomalous increase in the shear force demand on the tower walls above the podium is a major cause for concern. Design guidance on how to quantify these adverse effects is not available. In this paper a simplified method for quantifying the increase in the shear force demand on the tower walls is presented. In view of the very limited ductile nature of this type of construction the analysis presented herein is based on linear elastic behaviour.

• KDI Journal of Economic Policy
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• 제43권4호
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• pp.45-67
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• 2021

We analyze the social welfare effect when a policy-based financial system (PFS) enters a decentralized financial market. Particularly, the PFS in this case supports the interest spread for corporate loans held by firms with heterogeneous bankruptcy decisions under an imperfect information structure. Although support for capital costs through the PFS expands the economy consistently, the optimal level of PFS out of the corporate loan market is estimated to be 8.6% by a simulation model considering social welfare adjusted by the disutility of labor. This result is much lower than the recent level of PFS in the Korean financial sector.

• 대한조선학회 특별논문집
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• 대한조선학회 2007년도 특별논문집
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• pp.135-141
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• 2007

CSR(Common Structure Rules) enter into force on $1^{st}$ April 2006. Generally for double hull tankers of less than 150m in length, the Rules of the individual Classification Society are to be applied. Where high tensile stresses act through an intermediate plate, increased fillet welds or penetration welds are to be used longitudinal/transverse bulkhead primary support member end connections to the double bottom. If workers have begun to make used of established procedures between corrugated BHD and lower stool joint, first to welding on groove of face and then it has to gouging to blow on groove of root. So amount of man-hour increased, productivity secreased.

• Geomechanics and Engineering
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• 제13권1호
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• pp.173-194
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• 2017

Access shaft is of critical importance to the construction and operation of underground rock caverns. It usually has a relatively large cross-section and penetrates through fill materials, soil layers, and weathered rocks before reaching the caverns excavated in solid bedrock. In this paper, the design and construction of vertical shafts are reviewed in terms of diameter, depth, geological conditions, and support structure. Three shaft alternatives, namely alternative I: vertical shaft with spiral roads, alternative II: upper shaft with spiral roads & lower tunnels, alternative III: plain shaft, are proposed based on a simplified geological profile of the Jurong formation, Singapore. The advantages and limitations of the three types of shafts are discussed. The key issues relating to shaft design and construction, such as the shaft sinking, water control, support structure, are also discussed with a series of solutions provided, such as the sequential excavation, pre-grouting and diaphragm walls.

• 한국안전학회지
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• 제19권2호
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• pp.93-97
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• 2004

Slab formwork consists of sheathing, stringer, hanger and shore. There are several types of adjustable individual shores. In constructions site, pipe supports are usually used as shores. The strength of a pipe support is decreasing as it is frequently being used at the construction site. In this study, 2857 pipe supports were bought to fine out the strength change of used pipe support and unused pipe supports according to aging. Among these pipe supports, 2337 pipe supports were lent to the construction companies free of charge. Compressive strength was measured by knife edge test and plate test at each 3 month. Test results show that the strength of unused pipe supports almost equaled to the strength of new pipe supports until 191 days, but the strength of used pipe supports at 191 days was lower than the strength of new pipe supports. So, the strength of used pipe supports at 191 days was not satisfied the specification of KS F 8001. According to these results, it shows that attention has to be paid to formwork design using used pipe supports. Therefore, the paresent study results will be able to provide a firm base to design slab formwork and test the performance of used temporary structure and prevent formwork collapses.

• 한국지반공학회논문집
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• 제29권6호
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• pp.63-75
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• 2013

기존의 흙막이 공법의 문제점을 보완하고 개선하기 위해서 새로이 고안한 공법이 지주식 흙막이공법이다. 지주식 흙막이 공법은 전면지주와 배면지주를 사항으로 설치하여 일체화시킨 가시설 공법으로, 배면지주의 설치로 인해 전면지주에 작용하는 토압을 효과적으로 분산시켜 가시설의 구조적인 안정성을 증대시킨 공법이다. 본 연구에서는 점토지반의 실내모형실험을 통해 배면지주의 설치 여부와 지주 하부의 고정 조건 등을 달리하여 지주식 흙막이 공법의 역학적 특성을 확인하였다. 실내모형실험결과 배면지주의 설치로 인해 IER 벽체의 수평변위가 효과적으로 감소하는 것으로 분석되었으며, 배면지주의 간격 및 고정 조건에 따른 효과가 분석되었다.

• 한국공간구조학회논문집
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• 제12권3호
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• pp.71-78
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• 2012

공간구조물은 높이-경간비 또는 개각과 같은 아치의 형상비에 따라 상이한 동적거동특성을 나타내며, 이러한 공간구조물은 지진의 영향을 직접적으로 받는 하부구조의 강성 및 그 접합부에 따라 상이한 지진응답특성을 나타낸다. 따라서 본 연구에서는 수직진동모드와 수평진동모드의 영향이 다른 단층아치구조에 하부기둥의 강성과 접합부에 따른 지진응답특성을 분석하고자 한다. 하부기둥의 영향으로 단층아치구조는 수직방향 응답이 더 많은 영향을 받으며, 기둥의 접합부 회전강성에 있어서는 활절을 제외하고는 큰 영향이 없는 것으로 나타난다.

• 한국기계연구소 소보
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• 통권16호
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• pp.127-136
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• 1986

Recently deck crane of multi purpose cargo vessel (MPCV) is designed to posi¬tion in side instead of in the center line of the upper deck with a view to reduce the transportation cost and shipbuilding cost by shortening the length of ship. In this paper, the crane post was at first designed according to the crane maker’s specification and parent ship and the structure is analysed with Finite Ele¬ment Method. Through the careful reviews on the result of analysis, the final design of crane post was modified. The crane post is designed as a cylindrical in upper part and hexagonal in lower part instead of cylindrical on the whole as before. The connecting part of crane post is designed with the form of mixture of the cylinderical and hexagonal. Since the center of cylindrical and hexagonal section are not on the same line, it is expected to have the stress concentration. So, in order to attenuate the concentrated stress on the connecting part, the upper and lower parts was stiffened by inserting plate to enlarge the area of welding. The structure of deck part includes the tank side floor which is depend on the lower structure of the crane post that would support the force of the crane post by placing with 1.5 frame interval of the vertical plate.

• 한국공간구조학회논문집
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• 제10권1호
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• pp.95-102
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• 2010

공간구조물은 일반 라멘구조와는 다른 동적특성을 가지고 있으며 이런 동적특성에 관해 많은 연구가 수행되고 있다. 그러나 대부분의 연구는 특정 형태의 공간구조물에 대해 수행되었으며 내진설계를 위해 직접적으로 이용 가능한 연구결과는 매우 제한적이다. 본 연구에서는 공간구조물의 기본적인 동적특성을 내재한 트러스-아치구조물을 대상으로 양단의 기둥의 길이가 다른 경우에 트러스 아치구조물의 지진응답변화를 분석하고자 한다. 양단 기둥 길이의 차이에 따라 가속도 응답이 수평방향에 비해 수직방향에서 더 많은 영향을 받는다. 따라서 상부구조물을 지지하는 하부구조물의 강성이 다른 경우에 공간구조물의 내전설계에 있어서 수직방향 응답에 대한 고려가 더욱 많이 요구된다.