• Korean Journal of Construction Engineering and Management
• /
• v.10 no.4
• /
• pp.50-57
• /
• 2009

The Korea Standard of Estimate which has been used as the only basis of Cost estimate of public construction projects is failed to reflect the fluctuation of current construction cost. Therefore, the government decided to gradually introduce historical construction cost into cost estimate of public construction projects from 2004 and to reduce the use of Korean Standard of Estimate. This paper presents a series of process and the methodology for computing Actual Cost and analyzing the fluctuation patterns based on not only previous contract prices which made a successful bid but also all of the other bid prices. Also, this paper mainly handles a device for extracting strategic bid price such as low price bid for assuring reliable data and for predicting the construction cost which is built by Wavelet Analysis of Time series Analysis data and Neural Network. It is anticipated that the effective use of the proposed process for estimating actual unit cost would make the cost estimation more current and reasonable.

• International conference on construction engineering and project management
• /
• 2005.10a
• /
• pp.437-446
• /
• 2005

Recently as people's values are changing from development phase into running stage after quality of life, so that the needs of environmentally friendly construction are gradually increasing. Also populace discontent about the pollution during construction process such as the noise and vibration caused by construction machinery is increasing. Even though it is impossible to eliminate the construction pollution fully, it is necessary to make efforts to reduce construction pollution to a minimum. In terms of construction site operating, the first possible step for solving these matters directly is that the necessary sum of expenses must be secured as the environmental management costs in the conceptual phase. However, in fact, the environmental management costs have not been secured in the budget. Generally it is the major reason not arising proper activities to prevent the pollution in the construction site. The purpose of this research is to suggest the efficient budgeting method regarding Environmental management costs to ensure the necessary sum of environmental management expenses. To provide an efficient budgeting method, interviews with the person in charge of environment management was conducted. 78 construction sites was surveyed and environmental management costs were analyzed through their historical data from the survey. According to the results of analysis, the ratio of environmental management costs is revealed 0.45% of construction cost as average comparing 0.2% of legal limit. And usually the environmental management cost was appropriated into the safety management budget. So it is needed to isolate environmental management budget securely and modify the ratio of Environmental conservation Costs in Construction Technology Management Act.

• Journal of Korean Port Research
• /
• v.14 no.2
• /
• pp.165-173
• /
• 2000

Major factors that are considered to determine lease charges of container terminals are, among others, construction cost of berth, discount rate, financing cost, and size of annual equivalent recovery. This paper aims to calculate construction costs at PECT and GCT and their annual equivalent recovery on the basis of historical data, and to identify whether or not the relationship of the above result and current lease charges at the two terminals are justifiable.

• Proceedings of the KIEE Conference
• /
• 2004.05b
• /
• pp.148-151
• /
• 2004

When we have been estimated construction costs, till now, we are used to costs accumulating method of each items based on standard labors rates. But there are some problems of its methods. Our governments are applied to a historical construction costs estimation system fur building construction and civil engineering works from January 2004. The electrical construction works are forecasted that applied to historical construction cost estimation systems. This paper is supposed to reasonable estimation methods of overhead costs and profits.

• Proceedings of the KIEE Conference
• /
• 2004.05b
• /
• pp.176-179
• /
• 2004

When we have been estimated construction costs, till now, we are used to costs accumulating method of each items based on standard labors rates. But there are some problems of its methods. Our governments are applied to a historical construction costs estimation system fur building construction and civil engineering works from January 2004. The electrical construction works are forecasted that applied to historical construction cost estimation systems. This paper is summarized to roles and systems of quantity surveyor. And we investigated to activities and organizations of its associations.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.676-684
• /
• 2009

Decision making at the early stages of a construction project has a significant impact on the project, and various scenarios created based on the owner's requirements should be considered for the decision making. At the early stages of a construction project, the information regarding the project is usually limited and uncertain. As such, it is difficult to plan and manage the project (especially cost planning). Thus, in this study, a cost model that could be varied according to the owner's requirements was developed. The cost model that was developed in this study is based on the case-based reasoning (CBR) methodology. The model suggests cost estimation with the most similar historical case as a basis for the estimation. In this study, the optimization process was also conducted, using genetic algorithms that reflect the changes in the number of project characteristics and in the database in the model according to the owner's decision making. Two optimization parameters were established: (1) the minimum criteria for scoring attribute similarity (MCAS); and (2) the range of attribute weights (RAW). The cost model proposed in this study can help building owners and managers estimate the project budget at the business planning stage.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2007.11a
• /
• pp.261-266
• /
• 2007

In this research, we studied an estimating method in client's sight to estimate the total construction cost which is based on the historical cost data at the early stage of the office buildings as a public phase. It is very difficult to analyze the estimation accurately and logically. When a client estimates a project, he/she has to consider there are many issues at the planning step, according as office buildings become gradually diversified as well as their roles continuously extended. Therefore, those are usually make problems for wasting the budget in accordance with the cost estimation errors. Moreover, many kinds of public construction projects, especially such as school, office, sports complex, and the others, have been invested the private finances defined as BTL(Build Transfer Lease) method that are required to manage the detailed process more strictly from initial planning. In order to make an effective planning, the long-term users amount and the building life cycle at the beginning of project should be considered previously and then it may enable to achieve an appropriate project plan. But actually considering overall variables in a building planning is impossible. Accordingly, suggesting a regression model based on the historical cost data from many similar types of office building to support client's role known as estimating the total cost at the early stage. And then performing the test against the proposed model to research the reasonability as using the historical cost data of Japan office buildings.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• 2004.11a
• /
• pp.224-227
• /
• 2004

As a project progresses, it is well known that construction manager has to define the contingency for the expected project cost, which is used as a buffer for uncertainty. In this study, we mention uncertainty as the amount of likelihood that is difficult or impossible to predict project cost. From the completed work package, we obtain the true cost value, and this information is technically good data for estimating the realistic contingency of work packages to be accomplished. Based upon this historical information, construction manager recomputes the contingency for the remaining works. Conditional probability theory is often useful for re-estimating one of the remaining project progress as the true cost of the completed works can be different from the planned cost. As a project is progressing, true value is really important to predict the realistic project budget and to decrease the uncertainty. In this study, we gave applied conditional probability theory to estimating project contingency supposing a project that consists of fire work packages, provide the fundamental framework for setting and controlling project contingency.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.155-162
• /
• 2001

Recently, in Korea, a few construction companies have been tried to develop a management system, which is able to integrate schedule and cost. In spite of these attempts, however, advanced management techniques can be hardly applied under the BoQ based management system. In order to improve these problems, many studies have been peformed, but yet could not overcome practical limitations. Besides, the application of historical data is below the level since it is so difficult to accumulate and feed-back historical data under the unique character of construction industry. Consequently, lots of time and effort have being wasted to establish control criteria. The newly generated Information is not systematically managed as well. Therefore, this study suggests Integrated Construction Management System complemented the existing practical problems.

• Journal of the Korea Institute of Building Construction
• /
• v.14 no.5
• /
• pp.415-422
• /
• 2014

There is growing difference between a planned value and an actual cost for increasing as an risk of construction cost. A construction cost index is an alternative to redeem a problem, but it is still very difficult to reduce an actual differential as a price fluctuation. Furthermore an existing theory of a construction cost index is overly complex, and is unsuitable for using in working-level. This study suggests an optimum correction rate in respect of a total construction cost. It is analyzing the actual cost of 53 public buildings that the Public Procurement Service ordered. The objects are main processes that include architectural works, mechanical works, electrical works, telecommunication works, and service facilities. It is compared a total construction cost based on absolute error rate using the median from frequentist principle. For this, it is selected the suitable regression model and set a correction rate.