• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2439-2449
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• 2011

Existing grade crossings between railway and roadway area gradually changed to grade separation systems by the law. In the case of new roadway construction which crosses railways, it shall be grade separation system in principle. With the railway underground crossing method, many practices have been developed which can minimize rail displacements and avoid rail release. With these methods, the effects to the train can be reduced. The underground crossing methods can be identified as open-cut methods and non open-cut methods. The open-cut methods include temporary support methods and special rail construction methods. Also the non open-cut methods includes pipe roof methods, front jacking methods, messer shield methods, NTR methods and JES methods. Among these, the most suitable method is applied considering safety, economy, class of each rail system (train passing frequency and velocity), etc. In the non open-cut methods, the cost and duration shall be increased to keep existing rail system during construction. In the open-cut methods which use plate girders, the rail speed shall be restricted due to the displacement and vibration of the girder. In this study new grade separation methods were developed. With this method, the safety during construction can be increased. This method refines temporary support methods, but pc slab girder with huge stiffness is applied instead of plate girders. With this method, the rail displacement can be reduced and higher safety can be obtained during construction. Also construction cost and duration can be minimized because the temporary work and the overburden soil depth can be reduced.

• Steel and Composite Structures
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• 제32권3호
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• pp.325-336
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• 2019

Concrete placement and temporary formwork of bridge deck overhangs result in unbalanced eccentric loads that cause exterior girders to rotate during construction. These construction loads affect the global and local stability of the girders and produce permanent girder rotation after construction. In addition to construction loads, the skew angle of the bridge also contributes to girder rotation. To prevent rotation (in both skewed and non-skewed bridges), a number of techniques have been suggested to temporarily brace the girders using transverse tie bars connecting the top flanges and embedded in the deck, temporary horizontal and diagonal steel pipes placed between the webs of the exterior and first interior girders, and permanent cross frames. This study includes a rigorous three-dimensional finite element analysis to evaluate the effectiveness of several bracing systems for non-skewed and several skewed bridges. In this paper, skew angles of $0^{\circ}$, $20^{\circ}$, $30^{\circ}$, and $45^{\circ}$ were considered for single- and three-span bridges. The results showed that permanent cross frames worked well for all bridges, whereas temporary measures have limited application depending on the skew angle of the bridge.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.335-340
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• 2004

To analyze risk factors of temporary power installations, the investigation was carried out for power receiving system and pack and panel boards at construction sites. The subject was variable such as an airport, an apartment, a municipal playground. There are many risk factors caused by inadequate working environments and the deterioration of temporary power installations using equipment with minimum safety devices at construction sites. There, it is intended to present problems and preventive measures against electrical shock accidents, through analyzing risk factors of real field condition and investigating temporary power installations all over the country.

• 국제초고층학회논문집
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• 제8권3호
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• pp.185-192
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• 2019

Citic Tower is the first over-500 m-tall super highrise building in the world, located in the high seismic intensity area with paek ground acceleration over 0.2g in 475 years. This project is unique in its complexity, large volume, and challenging site conditions (zero site for construction). The traditional techniques can hardly meet safty, quality and schedule requirements of the construction. This article introduces the key construction technologies that are innovatively developed and applied in Citic Tower project construction, including intelligent super-high-rise building integrated construction platform system, independently developed by the CCTEB; Jump-Lift Elevator, which is the first of the kind with service height over 500 meters; combined temporary-and-permanent fire protection systems. The BIM technology is also applied in this project. Through technical innovation, and utilization of technologies, construction speed and safety had been greatly improved.

• 노동경제논집
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• 제31권1호
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• pp.1-27
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• 2008

본 연구는 최근 노동시장의 특정인 임시 일용직 증가의 원인을 분석하였다. 임시 일용직 증가 원인으로 기업의 수익성, 시장 변동성, 근로자의 자질에 대한 불확실성 측면에서 살펴보았다. 결과에 따르면 제조업의 경우 기업의 수익성과 건설업과 도소매업은 상품수요의 변동성과 관련이 깊은 것으로 나타났다. 한편 1990년대 이후 증가한 교육의 양적 팽창이 질적 향상을 수반하지 못한 결과 근로자의 자질에 대한 불확실성을 증가시키면서 기업은 상용직보다 임시 일용직을 선호하게 되었을 가능성도 간접적으로 확인되었다.

• 한국안전학회지
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• 제27권2호
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• pp.34-41
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• 2012

In this study, it has been proposed the new type of temporary bridge which is structural performance maximization to integrated cover plate and girder as well as roll of lining board. Of all temporary bridge integrated cover plate and main girder in the form of a new type of structure is advantageous for the judge, but to the field of transport difficulties and challenges due to high altitude operations to take advantage of this challenge and deliver a structured, easy transport, and the synthesis of lining board possible was proposed. Lining board proposed in this study through experimental synthesis and analysis of the factors that influence the effectiveness of the construction and economic development in the construction method was superior, compared to the conventional lining board.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.1350-1357
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• 2010

In tunnelling, temporary ventilation is very important factor in the safety of worker and the work efficiency which is affected by visibility. There are a lot of problems in the recent tunnel construction, because the longer the tunnel, the more the present design doesn't satisfy the allowable standard about dust and air pollution. Especially, In case the length of tunnel is more than 1,000m, the ventilation efficiency tends to decrease. In this study, the field measurement of the degree of contamination was performed near the face of tunnel. Based on the results obtained, the main factors of problem in temporary ventilation are the difference of temperature between outside and inside, the rate of leakage of ventilation duct and the dust and so on. It maybe helpful to the solution of problems, and also the accurate ventilation estimate.

• 한국건설관리학회논문집
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• 제18권1호
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• pp.83-89
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• 2017

가시설 공사는 자연환경에서 영구 구조물에 대한 시공을 수행하기 위해서 필요한 접근공간을 제공한다. 흙막이 공법과 같이 가시설 공사의 안정성을 높이기 위해서는 가시설에 작용하는 외부영향요인을 찾고, 이에 대응하기 위한 설계기능을 구현해야 한다. 즉 외부영향요인이 가시설 성능에 가져오는 영향을 최소화하기 위한 설계요소와 설계요소의 수준을 찾아야 한다. 본 연구에서는 가설공사의 대표적인 공법인 흙막이 공법을 대상으로 가시설 설계시 고려해야 할 외부영향요인을 분석하고, 영향요소를 최소화하기 위한 내부영향요인으로써 설계기능의 개선방안을 제시한다. 설계기능 구현시에는 다구찌 기법을 적용하여 설계요소에 대한 체계적인 평가를 실시하여 가치향상을 분석했다. 적용사례에서는 외부영향요인의 영향을 가장 적게 받으면서 제품특성의 목표치에 가장 근접한 설계인자의 조건을 찾았다. 시범사례에서는 다구찌 기법을 적용하여 흙막이 설계기능을 구현함으로써 외부요인의 변화에 적절하게 대응할 수 있는 설계기능을 제공할 수 있다는 것을 보여줬다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 추계 학술논문 발표대회
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• pp.128-129
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• 2018

With the increase of tall building construction, efforts for enhancing constructability are required from the pre-construction stage. Therefore, in this study, we proposed an evaluation method of constructability performance by performing construction engineering activities at the design phase. Based on some results of previous studies, we estimated the importance of design factors and categories influencing the constructability in each engineering activity related to temporary work and then presented a method for evaluating the constructability performance of design alternatives.

• 한국관광식음료학회지:관광식음료경영연구
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• 제13권1호
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• pp.81-110
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• 2002

The temporary tax deduction on investment cutting the corporate income tax within 10% of the amount of investment is aimed at stimulating the investment for economic activity. 25 business sectors are applied to this tax law and in tourism, the accommodation registered by tour promotion law and international convention plan business belong to it. I'd like to mention the problem of the temporary tax deduction on investment amount for hotels and suggest better solutions. This tax law is so temporary applied that we shouldn't get tax deduction after June 30, 2002. So, we can't get income tax deduction on the investment out of the available period. And further more this tax law has a rule not real investment but solely new project investment for hotels. There are numbers of difference between real investment and new project investment. The amount of investment is based on an object of acquisition taxation. And also there are numbers of difference between real investment and an object of acquisition taxation. For example, landscape construction is a great part of hotel construction but it's not an object of acquisition taxation. For running hotel business, we also need lots of equipments such as linens utensils for restaurant and decorations for hotel interior. But these are also excluded from this tax law. As you know, these equipments can be regarded as product equipments in manufacture industry. Therefore we should take the specificity of hotel investment into consideration and expand the role of the temporary income tax deduction on investment amount for hotels.