• Journal of KIISE:Software and Applications
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• v.37 no.2
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• pp.95-103
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• 2010

Improving the competitiveness of software products in the market involves procuring the means to design software architecture that deliver qualities necessitated by stakeholder requirements within allocated budget, thereby improving the cost-effectiveness of the end product. Currently, software architecture evaluation methods are used to predict and review qualities inherent in software architecture designs and to choose a candidate architecture that delivers desired qualities. Existing software architecture evaluation methods, however, fail to address the cost considerations dependent on the architecture chosen for product implementation. In this paper we suggest a cost estimation method for software architecture which adapts the cost drivers in the software cost estimation model COCOMO II to support cost estimation during architecture evaluation. The suggested method can be performed in coordination with existing software architecture evaluation efforts and supplements existing architecture evaluation techniques with guidelines for identifying and evaluating cost drivers in candidate software architectures without incurring extra overhead. The accuracy of the cost estimation using the suggested method is verified through application of the method to the architecture candidates used in RPS (Robot Patrol System), a surveillance embedded system.

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.2
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• pp.106-118
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• 1992

The landscape architecture construction cost estimation includes the repeated calculation and updating. Thus, it is time-consuming, and one of the jobs which needs to be automated first. In Korea, the IBM compatible personal computer(PC) is the most widely used one in the landscape architecture firms. However, the software for landscape architecture construction cost estimation is not being used in the PC environment. Therefore, the purpose of this study is to develop the software which can be used to automate the calculation for the landscape architecture construction cost estimation, and runs in the IBM compatible personal computers(PC). The clipper '88 summer is one of the DBMS software packages, and it has many commands and functions and functions which reduces program lines and makes the programing efficient, especially in the programing work whose total source code lines do not exceed over 10,000 lines. So, it was used in this study. The software developed in the this study was tested using the real data, and it was found that it can be efficiently used in the following jobs. They are: (1) to calculate exactly and rapidly. (2) to use resources repeatedly. (3) to print out the results. (4) to store data files for the future use. The software, as discussed in this paper, reduces the time and efforts to be spent in the calculation for the landscape architecture construction cost estimation compared with the traditional approach using the pocket calculator.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.475-478
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• 2013

To carry out a one-off construction project successfully, effective and accurate early cost estimation is crucial, especially during the conceptual stage where very limited minimum information of construction project is given. As the level of accuracy of the early cost estimation has huge impacts on precise budgeting and cost management of a project, in other words, reducing the risk of a project, cost must be managed with special awareness. In an effort to improve the estimate accuracy of cost during the conceptual stage, this research introduces a Parameter Impact (PI) which can quantify weights of parameters and rank them; and PI development derived from the principle of impulse in physics is explicated. For a case study, 76 public apartment building cases in Korea are analyzed. To examine the validity of the proposed PI, a validation in terms of CBR applicability test and estimate accuracy comparisons using 10-nearest neighbor cases are carried out. The validation results support that the suggested PI can be applied in quantifying the weights of the parameters and CBR method for early cost estimation.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.597-598
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• 2015

In order to improve the reliability of cost estimation results using CBR, there has been a continuous issue on similarity measurement to accurately compute the distance among attributes and cases to retrieve the most similar singular or plural cases. However, these existing similarity measures have limitations in taking the covariance among attributes into consideration and reflecting the effects of covariance in computation of distances among attributes. To deal with this challenging issue, this research examines the weighted Mahalanobis distance based similarity measure applied to CBR cost estimation and carries out the comparative study on the existing distance measurement methods of CBR. To validate the suggest CBR cost model, leave-one-out cross validation (LOOCV) using two different sets of simulation data are carried out. Consequently, this research is expected to provide an analysis of covariance effects in similarity measurement and a basis for further research on the fundamentals of case retrieval.

• Land and Housing Review
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• v.1 no.1
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• pp.1-7
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• 2010

Case-based reasoning (CBR) method can make estimators understand the estimation process more clearly. Thus, CBR is widely used as a methodology for cost estimation. In CBR, the quality of case retrieval affects the relevance of retrieved cases and hence the overall quality of the reminding capability of CBR system. Thus, it is essential to retrieve relevant past cases for establishing a robust CBR system. Case retrieval needs the following tasks to obtain appropriate case(s); indexing, search, and matching (Aamodt and Plaza 1994). However, the previous CBR researches mostly deal with matching process that has limits such as accuracy and efficiency of case retrieval. In order to address this issue, this research presents a CBR cost model for building projects that has two-step retrieval process: decision tree and nearest neighbor methods. Specifically, the proposed cost model has indexing, search and matching modules. Features in the model are divided into shape-based and scale-based attributes. Based on these, decision tree is established for facilitating the search task and nearest neighbor method was utilized for matching task. In regard to applying nearest neighbor method, attribute weights are assigned using GA optimization and similarity is calculated using the principle of distance measuring. Thereafter, the proposed CBR cost model is developed using 174 cases and validated using 12 test cases.

• Journal of The Korean Digital Architecture Interior Association
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• v.10 no.3
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• pp.11-18
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• 2010

Cost estimation through fast and correct quantity take offs are crucial in the process of construction project. The existing methods for cost estimation are mainly based on 2D-based drawings and the estimation result tends to be different according to the estimator's experience, the quality and quantity of used information and estimation time. To solve these problems, the domestic construction industry have recently tried to use the data extracted from 3D data modeling based on BIM(Building Information Modeling) in order to achieve more accurate and objective cost estimation. However it tends to increase dramatically the quantity of information that can be used in cost estimation by estimators. Therefore in order to achieve quality information data from 3D data modeling, the characteristics of the project should be reflected on the 3D model and it is most important to extract information only for cost estimation from the whole 3D model fast and accurately. Thus this study aims to propose the 3D modeling method through Data Normalization which maximizes the usability of 3D Data modeling in cost estimation process.

• International conference on construction engineering and project management
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• 2009.05a
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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.

• Journal of the Society of Naval Architects of Korea
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• v.46 no.3
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• pp.351-361
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• 2009

Many manufacturers define the system of a new product flexibility, and take advantage of previous-product information using the product configuration concept. Product configuration is an approach that defines the system of a new product centered on the product structure by referring to the previous-product information. In this paper, it is established how to apply the concept of a product configuration utilizing previous-ships information in construction cost estimation process systematically and effectively. For this, we define the advanced-construction cost estimation process based on a naval ship product model, and design construction cost estimating model. It is validated that this process and model have the applicability through the case study of the construction cost estimating of the mine-warfare ship.

• Architectural research
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• v.7 no.1
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• pp.11-18
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• 2005

In today's building industry the emphasis has been geared more towards construction, thus building maintenance and life cycle have been neglected until now. A direct result of this neglect is the rapid aging of building, which leads to more cost-effective decision making methods for the prolongation of building life span. The following study is conducted in the area of Daegu and Seoul in order to develop the estimation analysis method of the annual operation cost of the Korean high-rise condominiums for the cost-effective decision making support through mathematical and statistical analyses including the present value and standardized measurement corrections. Based on the assumption that the life expectancy of the high rise condominium is 50 years, initial cost is ￦421,212/$m^2$, and a total sum of yearly operation cost during life expectancy is ￦2,154,499//$m^2$), yearly accumulated operation cost is shown as below: $AOC=0.7097t^4-38.803t^3+806.95t^2+11045t-496.52$ ($R^2=0.98$) (Here, AOC = Accumulated Operation Cost, t = given years)

• International Journal of Naval Architecture and Ocean Engineering
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• v.4 no.3
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• pp.291-301
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• 2012

A scalar metric for the assessment of hull surface producibility was known to be useful in estimating the complexity of a hull form of ships or large offshore structures by looking at their shape. However, it could not serve as a comprehensive measuring tool due to its lack of important components of the hull form such as longitudinals, stiffeners, and web frames attached to the hull surface. To have a complete metric for cost estimation, these structural members must be included. In this paper, major inner structural members are considered by measuring the complexity of their geometric shape. The final scalar metric thus consists of the classes containing inner members with various curvature magnitudes as well as the classes containing curved plates with single and double curvature distribution. Those two distinct metrics are merged into a complete scalar metric that accounts for the total cost estimation of complex structural bodies.