• International conference on construction engineering and project management
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• 2017.10a
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• pp.133-137
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• 2017

Nuclear power plants in Korea are usually built based on a duplicated model; so the project cost data of the preceding unit can be used as reference when estimating the project cost for the succeeding unit. However, since the contracting method is oriented towards the price, empirical factors such as making top-down estimations using the reverse calculation method based on the completion cost of the preceding unit is dominant. In order to develop a project cost database to resolve such problems, the detailed cost boundary of the project cost data must be categorized by project and by system. This study proposes a method to connect the code of account with the base quantities and the IAEA account, and proposes a database structure for the development of a project cost estimation system. The estimation system developed in the future is expected to utilize the proposed project cost data structure.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.445-450
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• 2002

In this paper, FEM analysis is peformed in order to estimate the behavior of RC columns retrofitted with Carbon Fiber Sheet(CFS). Five specimens with different quantity of CFS are analyzed and compared with experimental results. The analytical results show that FEM can be used to predict the shear behavior of columns retrofitted with CFS.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.671-674
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• 1999

With increasing content of granulated blase furnace slag in cement, the content of capillary pores in the mortar decreases and later age strength of the concrete. Therefore, this provides greater reserves study is carried out to estimate frost resistance of high-strength concrete specimens with water cement ratios using blast-furnace slag. 1. Blast furnace concrete is comparatively more good frost resistance than normal concrete. 2. As the blast furnace slag increases, the quantity of pores with a radius of more than 30nanometer decreses.

• International Journal of Reliability and Applications
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• v.1 no.1
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• pp.81-87
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• 2000

One of the most important quantities in reliability theory is the expected number of renewals of a system during a given interval. This quantity, the renewal function, is used to determine the optimal preventive maintenance policy and to estimate the cost of a warranty. In this paper we study a parametric approach for a renewal function. The simulation study is presented to compare the relative performance of the introduced estimators of a renewal function. And we show that the proposed parametric estimator performs well.

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.677-679
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• 1993

The necessary parameter and states for the field-oriented control scheme of induction motor have been correctly estimated by EKF(Extended Kalman Filter). In this paper, Reduced-Order EKF(Extended Kalman Filter) is proposed tn estimate rotor speed and rotor flux. It is profitable in the implementation of field-oriented control scheme rather than Full-Order EKF because of saving operational quantity. The simulation results show that the proposed Reduced-Order EKF is excellent performance.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.6
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• pp.2519-2528
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• 2013

The standard of estimate is being used as basic material for appropriating construction expenses of public institutions and private institutions. The present thesis aims to propose a new form of a standard of estimate and a calculation method of work amount of equipment by targeting a representative construction type selected at river reservation work. The present thesis expects that the convenience of users can be expanded by improving applicability of a standard of estimate and simplifying a calculation process of work amount of equipment in a process planning stage so that the provision of work crew lineup information and daily productivity information is possible by a standard of estimate. In case of river conservation work, because the variables called work conditions act very largely, there exists much difficulty for generalizing productivity information and work amount of equipment, but if its accuracy could be enhanced by improving continuous productivity information and work amount information of equipment, the simplification of process planning establishment and cumulative process through a standard of estimate would be possible.

• Korean Journal of Construction Engineering and Management
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• v.9 no.4
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• pp.131-139
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• 2008

Now, one of the greatest concerns at home and abroad is eco-friendly construction. Above all, the reduce and recycle of the construction waste may be one of the most important things. The construction waste has been produced most at demolition phase, but the research into that area has not being to make nearly within the country. Recently, as the government have realized the importance of that area, they are making research to improve traditional demolition methods. Also, they are preparing to make a raw to enforce deconstruction during demolition phase. This research has analyzed the problems and waste types which produced during the demolition works by surveying in site. Until now, in the interior, the right quantity basis has not been suggested, because of the absence of any methods to estimate it accurately. Therefore, this study has compared and analyzed owner's ordering quantity, drawing analysis quantity with measuring the waste to produced at site during demolition works, this research results are expected to be the important materials for future research into the construction waste area.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.730-731
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• 2015

This study aims at giving the framework to estimate the environmental load at planning and schematic phase. With increasing awareness of environmental issues, the effort to reduce the environmental impacts caused by human activity has been increasingly enlarged. So far most of researches estimating CO₂ emissions have analyzed energy consumption based on BOQ (Bills of Quantity) acquired after detailed design. There is also lack of reliability in the estimated environmental impact using the basic unit of a facility at the planning stage, because it uses a limited specific section of historical data. Thus, this study is targeted at developing framework to assess reliable environmental loads based on information available at project early phases by making case-bases from historical design information on PSC Beam Bridge. Historical database is built on the basis of the LCA (Life Cycle Assessment) and in order to set input information for estimating model, the literature about information in an early project phase are reviewed. Using the information available in the planning and schematic design stage, the Framework is presented to estimate the environmental load in an early stage in the project. Developing an environmental load estimation model in accordance with the Framework presented in this study, it is expected that the environmental load in the initial project phase can be estimated more quickly and accurately.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.7204-7210
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• 2015

This paper has developed the system for supporting the approximate construction cost and the quantity estimation based on 3D model information in the pre-project planning phase of 3-span continuous cable-bridge with 2-pylons. First of all, we'd analyzed the design information (structural design report, blueprint and quantity) of the existing cable-stayed bridges and derived the design variables of cable-stayed bridges. We developed the BIM wizard that generates a cable-stayed bridge model parametrically based on derived design variables. The principle material quantities of cable-stayed bridge are calculated directly from 3-dimensional bridge model built by using the BIM wizard. Then, we can estimate the construction cost in relation to its quantities and unit cost of cable-stayed bridge. In a result, we have established the system that the construction cost can be estimated more specific than the conventional method (construction estimates per meter or square meter). We hereby will be able to review various alternatives as soon as possible in bidding process.

• Korean Journal of Construction Engineering and Management
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• v.10 no.2
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• pp.111-120
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• 2009

The conceptual cost estimation used the construction project needs for confirm budget not only at the planning phase but also at the preliminary design phase of the construction project. Present, the conceptual cost estimation model have problems the rate of error is very large because the linear simple model calculate by use the cost of the unit meter or the unit square. This study development the model used grouping and the key quantity method, the mixed unit cost for solve problem of the very large rate of error. The result of this study reduced difference of between the real design construction cost therefor it expect that contribute to the client or the service company estimate budget of RC rahmen bridge.