• Korean Journal of Construction Engineering and Management
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• v.11 no.4
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• pp.22-31
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• 2010

Because the estimated cost at early stage has great influence on decisions of project owner, the importance of early cost estimation is increasing. However, it depends on experience and knowledge of the estimator mainly due to shortage of information. Those tendency developed into case-based reasoning(CBR) method which solves new problems by adapting previous solution to similar past problems. The performance of CBR model is affected by attribute weight, so that its accurate determination is necessary. Previous research utilizes mathematical method or subjective judgement of estimator. In order to improve the problem of previous research, this suggests CBR schematic cost estimation method using genetic algorithm to determine attribute weight. The cost model employs nearest neighbor retrieval for selecting past case. And it estimates the cost of new cases based on cost information of extracted cases. As the result of validation for 17 testing cases, 3.57% of error rate is calculated. This rate is superior to accuracy rate proposed by AACE and the method to determine attribute weight using multiple regression analysis and feature counting. The CBR cost estimation method improve the accuracy by introducing genetic algorithm for attribute weight. Moreover, this makes user understand the problem-solving process easier than other artificial intelligence method, and find solution within short time through case retrieval algorithm.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.614-617
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• 2004

The construction industry is typical of the ' job of 3D ', the automated construction equipments are getting used in the domestic construction sites and the construction robots began to be sold in the abroad. The research developed the small sized robot which could be used at the apartments and the office buildings with the small floors. But the past finishing robot could not be operated easily, it had expensive controller which could not increase the production of robot. In this paper, user interface is made to operate easily the small concrete floor finishing robot with two trowel which has low cost controller, motion algorithm including modeling and mechanism about the concrete finishing robot is developed to control moving. Simulation and experiment figure out how the finishing robot moves and will contribute to realizing it.lizing it.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.527-532
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• 2005

The construction industries are facing problems of productivity, quality of work, safety, and the completion of projects in time. In construction industry a worker is exposed to hazardous environment, and has to do more physical work, effecting his health and also productivity. The automation and robotics can offer solution to many problems of the industry. In the past the major barrier to construction automation is the lack of electronic components and systems. This is solved now with the development of information technology, and the current obstacle is the high cost of automated systems, shortage of public money for R&D, and problems of acceptance. The robots employed in construction have followed the same concept as those employed in manufacturing. However, construction industry requires a different kind of robot compared to manufacturing Industry. The robots are stationery and product moves along the assembly line in manufacturing sector, but construction robots have to move about the site because buildings are stationary and of large size. The construction robots must function in adverse weather conditions, including variation in humidity, and temperature and increase the overall construction productivity rate. The major objective of the paper is to review the existing applications of building robots and to assess their implementation in building industry. A case study is considered for the implementation of robots for the painting work of the University Building at Saifabad PG College of Science, Hyderabad, India.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1531-1535
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• 2008

In the past vertically integrated power system, the power utility forecasted power demand and invested new power plants to keep a system adequacy. However, in the competitive electricity markets, a principle part of the capacity investment is market participants who decided the investment to maximize their profit. Especially, one of the main factors in their long-term decision making is the retrieval of fixed costs (construction costs). This paper presents the capacity payment in electricity power markets. The capacity payment (CP) in Cost Based Pool (CBP) is needed to recover fixed costs. However, CP in CBP was applied not only recovering fixed costs but also ensuring supply reliability. In order to operate harmonious power markets, pool needs reasonable CP mechanism. This paper analysis CP using capacity proportion and Reliability Pricing Model (RPM).

• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.4
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• pp.185-195
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• 2001

Latex Modified Concrete(LMC) has been widely used for the pavement of highway bridges over the past 35years around the world since it is more resistant to the intrusion of chloride ions, has higher tensile, compressive, and flexural strength, and has greater freeze-thaw resistance. However, in Korea, it has not been introduced to fields due to higher initial construction cost for its overlay compared with that of conventional pavement materials. Due to durable characteristics, it should be noted that the LMC may be more cost-effective than conventional pavements such as asphalt pavement, when life-cycle cost(LCC) concept is considered. The objective of this study is intended to suggest a practical LCC analysis model for pavement projects and to demonstrate relative cost-effectiveness of the LMC overlays in comparison with conventional pavement techniques. It may be stated that the procedure proposed in this study may be utilized for making optimal decision on cost-effective pavement design.

• Korean Journal of Construction Engineering and Management
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• v.10 no.6
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• pp.135-145
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• 2009

The main goal of construction projects from the past has been enhancing efficiency by reducing cost and time. but, seeing the current condition of safety management of many construction companies nowadays, it is true that not much attention has been paid to safety management for a long time. However, there are paradigm shift from the cost and term of works to safety management in the construction industry, from this circumstance the safety management is evaluated more importantly. Though less accident happens compared to past, the accidents are getting greater because construction projects nowadays are bigger and more complex and monetary loss from the accidents are increasing. Also, the severity is getting greater and even fatal. For this reason, more improved safety management is very necessary. Therefore, we are to propose more efficient system for safety management in this thesis. Technical parts for developing system include many technique such as Real Time Locating system, and other techniques like Monitoring module based on BIM, Data Mart, Alarm are also applied together. Through this system, in the construction site, safety management is performed more effectively and widely because the system can manage the human resource and fluid situation. Also, safety manager can conduct more systematically and advanced safety management through human resource dominated safety management.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.29-37
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• 2015

Multi-household buildings are efficiently maintained from the mid- and long-term viewpoint according to the long-term repair coverage system etc. On the other hand, public buildings are not systematically maintained due to a lack of past maintenance cost data and inefficient budget plans, among other problems. Targeting public buildings in Incheon, this study analyzed operation costs variables. To verify the analysis results, they underwent a correlation analysis and a multi-regression analysis. With regard to public buildings electricity, gas and tap water cost, the influence power of the served life, floor area, and workforce were analyzed, revealing that electricity cost was highly correlated with workforce, while gas and tap water cost were correlated with tap water cost. Also, the correlation analysis results were verified through a multi-regression analysis, and a maintenance cost estimation model was presented using a regression equation.

• Journal of Korean Society of Steel Construction
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• v.19 no.1
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• pp.15-27
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• 2007

Over the past decade, labor costs have increased relative to the cost of material hardware according to analysts in the construction industry. Therefore, the minimum weight design, which has been widely adopted in the literature for the optimal design of steel structures, is no longer the most economical construction approach. Presently, although connection- related costs is crucial in determining the most cost-effective steel structures, most studies on this subject focused on minimum-weight design or engaged in higher analysis. Therefore, in this study, we proposed a fabrication scheme for the most cost-effective moment-resisting steel frame structures that resist lateral loads without compromising overall stability. The proposed approach considers the cost of steel products, fabrication, and connections within the design process. The optimal design considered construction realities, with the optimal trade-off between the number of moment connections and total cost was achieved by reducing the number of moment connections and rearranging them using the combination of analysis that includes shear, displacement and interaction value based on the LRFD code and optimization scheme based on genetic algorithms. In this study, we have shown the applicability and efficiency in the examples that considered actual loading conditions.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.25-32
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• 2022

As a project delivery method, Design-Build (DB) has provided owner, architect, and contractor groups with a process of early design and rapid construction for the past three decades. Although there are many benefits to using standard DB, dissatisfaction has arisen due to limitations to innovate, limited owner involvement during design, and often lengthy procurement. Progressive Design-Build (PDB) has become an appealing alternative providing benefits not seen with standard DB. This paper investigates how PDB impacts a project and how it compares against standard DB; it also presents a proposed framework for evaluating the owner's responsibility and assessment of a project, which we named the "Four Pillars of Project Success". The four pillars are defined with respect to an owner's responsibility and assessment of a project, including project predictability, project risk, project schedule, and project cost. We conducted a literature review, examined several public project case studies, analyzed PDB project information collected by the Design-Build Institute of America (DBIA), and held stakeholder interviews with owners, contractors, and architects who have used both PDB and standard DB. This paper offers insight into PDB's structure and outcomes so an owner group can make an informed decision when considering PDB as their next construction contracting method.

• Journal of the Korea Institute of Building Construction
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• v.17 no.5
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• pp.473-481
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• 2017

With the barracks modernization project, the Ministry of National Defense has been operating 60 projects of the 75 that have been announced. It was difficult to investigate and analyze the data in the past because data could not be obtained while it was much easier to do that since data can be obtained from private companies. With the aim of increasing the usability of the facilities, the objective of this study is to present a reasonable alternative for repair and maintenance costs by investigating and analyzing the budget and the actual expenses of repair and maintenance of military facilities for the past 3 to 5 years, and then identifying the problems with these. To accomplish this, a theoretical review of previous studies and legal grounds related to repair and maintenance costs was performed, and data on the estimates and the actual expenses data used in BTL projects carried out by private companies were analyzed. First, one of the problems was that there are some items omitted, including consumables, and these items should be included in order to secure their budget. Second, in terms of the items for divided payments, two improvements had been presented: a short-term payment plan for the operation period of 3 to 5 years and a long-term payment plan for an additional and complemented period other than the operation period. The repair and maintenance costs should be further studied at the point of time in a future when the actual data on the costs and operation period of military facilities can be secured. This study is expected to serve as empirical data that will form the basis for a reasonable calculation of the construction cost for military facilities.