• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.488-493
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• 2013

Accurate initial cost estimates are essential to effective management of construction projects where many decisions are made in the course of project management by referencing the estimates. In practice, the initial estimates are frequently derived from historical actual cost data, for which standard distribution-based techniques are widely applied in the construction industry to account for risk associated with the estimates. This approach assumes the same probability distribution of estimate errors for any selected estimates. This assumption, however, is not always satisfied. In order to account for the probabilistic nature of estimate errors, an alternative method for measuring the risk associated with a selected initial estimate is developed by applying the Bayesian probability approach. An application example include demonstrates how the method is implemented. A hypothesis test is conducted to reveal the robustness of the Bayesian probability model. The method is envisioned to effectively complement cost estimating methods that are currently in use by providing benefits as follows: (1) it effectively accounts for the probabilistic nature of errors in estimates; (2) it is easy to implement by using historical estimates and actual costs that are readily available in most construction companies; and (3) it minimizes subjective judgment by using quantitative data only.

• Composites Research
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• 제19권5호
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• pp.34-39
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• 2006

The mechanical properties and durabilities of fiber advanced composites make them ideal for widespread applications in construction worldwide. However, one of the problems of fiber reinforced advanced composites has expensive initial costs. So the efforts for lowering the initial cost have to be needed. There has been hardly assessment results of life cycle cost for fiber reinforced advanced composites in construction field, but some papers showed that total life cycle cost could be profitable, if the initial cost could be reduced. The purpose of this paper is to report assessment results of LCC(Life Cycle Cost) for application of FRP(Fiber Reinforced Plastic) in construction field.

• 한국지반환경공학회 논문집
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• 제8권3호
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• pp.11-18
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• 2007

본 연구에서는 파급효과가 큰 공동주택에서 지열 냉난방 시스템의 경제성을 아파트 분양평형, 운전시간, 냉난방 및 급탕 설치형태별로 구분하여 초기 공사비 증가, 운전비 절감액, 초기 투자비 회수기간등을 산정하였다. 냉난방 및 급탕 운전시간이 많을수록 초기 공사비 증가액에 비해 운전비용 절감액이 커 초기 투자비 회수기간이 단축되었다. 전용면적이 클수록 투자회수 기간이 길었으며 냉난방 및 급탕 설치형태에서는 냉난방을 지열원, 급탕을 폐열회수한 경우가 초기 투자 회수기간이 가장 짧았다. 기존 시스템(패키지 에어콘, LNG 난방 및 급탕)에 비해 냉난방, 급탕을 모두 지열로 이용하는 경우, 냉난방은 지열, 급탕은 폐열을 이용하는 경우, 냉난방은 지열, 급탕은 LNG인 경우에 공사비가 $m^2$당 각각 약 72,000원, 66,900원, 62,300원 정도 증가하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.329-330
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• 2021

The calculation of the correct construction value in the construction should be investigated after the quantity is calculated. In order to calculate the quantity requires a lot of cost and time, and the initial accurate quantity calculation is not possible. Therefore, in the planning step in order to successfully complete the project to demonstrate the practicality of the difference between the construction cost by the construction design by presenting a method for calculate the quantity through the estimate with the construction open, floor plan, surface view, section.

• Composites Research
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• 제19권1호
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• pp.43-48
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• 2006

High performance fiber reinforced cement composites have better performances than traditional cement based materials, therefore, have been expected as new construction applications such as the materials for construction & bridge structure, repair and rehabilitation applications, anti-collapse applications, anti-noise applications etc. However, they have lots of the problems such as material design, fabrication method and structural analysis. Also, the most serious problems of High performance fiber reinforced cement composites have been expensive initial cost, lack of long-term exposure data. As a result, it is needed that the efforts for lowering the initial cost and accumulation of long-term exposure. There has been hardly assessment results of life cycle cost for HPFRCC in construction field, but some papers showed that total life cycle cost could be profitable if the initial cost could be reduced.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.400-405
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• 2011

The total length of Korean urban railways reaches 1,200km. Urban railway used to be installed with ballasted tracks by reason of low cost at the time of construction, slab tracks are now being installed due to the reasons of the improvement in safety, lengthening service life and more economical method in terms of maintenance. The length rate of slab tracks has exceeded 70% of the domestic urban railways with the methods ranging from STEDEF, LVT, ALT, Eidan-type, B2S to RHEDA. This study surveyed the share of domestic slab tracks, and compared and evaluated the input cost at the initial stage by the types of slab tracks. Construction processes have been standardized by the existing design documents and calculated the initial input cost for the length of 1km of a hypothetical straight line. Cost breakdown structure was evaluated as materials cost, construction cost, equipment cost, indirect cost, etc. It is expected that this study will be used in selection & evaluation which is considering the economic feasibility of slab tracks.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1242-1247
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• 2009

The sudden changes in the construction market and the progressively intensifying price wars have amplified the importance of the construction cost estimation in the initial and planning phases of construction projects. However the methodologies and process of estimating construction cost in the planning and design phase are not standardized in the domestic market, in contrast to the markets of more developed countries. Therefore this paper proposes a new approximate estimation model to be used from the initial stages of construction projects. This methodology that extracts, modifies and synthesizes comparable elements of previous cases. This will introduce the foundation for the implementation of systems with improved usability and applicability.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.87-88
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• 2016

In order to assess the design value of engineering work from the point of view of LCC (Life Cycle Cost) in Korea, it is mandatory for all construction works that the total construction costs are over 10 billion won. The LCC includes initial construction costs, maintenance & operation costs, energy costs, end-of-life costs, and so on. Among these, the portion for maintenance & operation costs for a building is sizeable, as compared to the initial construction costs. Furthermore, the paradigm for construction industry has rapidly shifted from 2D to BIM, which includes design planning and data management. However, the study of BIM-based LCC analysis is not adequate today, even though all domestic construction projects ordered by the Public Procurement Service have to adopt BIM. Therefore, this study suggests a methodology of BIM-based LCC analysis that is particularly focused on repair and replacement (R&R) cost. For this purpose, we defined requirements of calculating R&R cost and extracted X from the relevant IFC data. Thereafter, we input them to the ontology of calculating the initial construction costs to obtain an objective output. Finally, in order to automatically calculate R&R cost, mapping with R&R criteria was performed. We expect that our methodology will contribute to more efficiently calculate R&R cost and, furthermore, that this methodology will be applicable to all range of total LCC. Thus, the proposed process of automatic BIM-based LCC analysis will contribute to making LCC analysis more fast and accurate than it is at present.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.417-424
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• 2009

For a construction project to progress smoothly, effective cost estimation is vital, particularly in the conceptual and schematic design stages. In these early phases, despite the fact that initial estimates are highly sensitive to changes in project scope, owners require accurate forecasts which reflect their supplying information. Thus, cost estimators need effective estimation strategies. Practically, parametric cost estimates are the most commonly used method in these initial phases, which utilizes historical cost data (Karshenas 1984, Kirkham 2007). Hence, compilation of historical data regarding appropriate cost variance governing parameters is a prime requirement. However, precedent practice of data mining (data preprocessing) for denoising internal errors or abnormal values is needed before compilation. As an effort to deal with this issue, this research proposed a statistical methodology for data preprocessing and verified that data preprocessing has a positive impact on the enhancement of estimate accuracy and stability. Moreover, Statistically Preprocessed data Based Parametric (SPBP) cost models are developed based on multiple regression equations and verified their effectiveness compared with conventional cost models.

• 한국건설관리학회논문집
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• 제17권5호
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• pp.54-61
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• 2016

건설프로젝트에서는 초기에 계획된 년차별 사업비가 공사 수행과정에서 빈번히 조정된다. 년차별 사업비가 초기 계획보다 감소되면 수행가능한 공정도 초기 공정계획대비 감소하게 되므로, 변동 사업비 내에서 수행가능한 적정한 공정을 재수립하여야 한다. 그러나 대다수 현장에서는 공정 재수립 없이 당초계획대로 공정을 진행하면서 사업비가 소진되면 현장 작업을 쉬는 경우가 많다. 이에 본 연구에서는 변동된 사업비 내에서 적정 공정계획을 재수립하고, 재수립된 일정에 따라 비용투입현황을 시각화하는 능동형 5D CAD 시스템을 개발한다. 이는 공정계획 재수립을 위한 의사결정 지원도구로 활용될 수 있고, 기존의 단순 시각적 정보제공에 중점을 둔 5D CAD시스템의 실무 적용성을 높일 수 있을 것이다.