• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.653-659
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• 2018

The accurate prediction of construction cost is a key factor in a project's success. However, it is hard to predict the construction costs in the planning stages rapidly and precisely when drawings, specifications, construction cost calculation statements are incomplete, among other factors. Accurate construction-cost prediction in the planning stage of a project is also important for project feasibility studies and successful completion. Therefore, various techniques have been applied to accurately predict construction costs at an early stage when project information is limited. There are many factors that affect the construction cost prediction. This paper presents a construction-cost prediction method as multiple regression model with seven construction factors as independent variables. The method was used to predict the construction cost of a local housing union project, and the error rate was 4.87%. It is not possible to compare the cost of the project at the planning stage of the local housing union project, but it has high prediction accuracy compared to the unit price of an existing unit area. It is likely to be applied in construction-cost calculation work and to contribute to the establishment of the budget for the local housing union project.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1215-1224
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• 2013

Great efforts have been made worldwide to reduce the Green House Gas (GHG) emission following the "Kyoto Protocol" declared during the United Nations Framework Convention on Climate Change in 1997. Many industries have restructured to meet the standard set by the Protocol. However, no clear guidance has been established for the purpose of reducing the GHG emission in construction industry. In addition, no significant effort has been made to conserve the energy during construction activities. For more effective energy saving in construction industry, it is essential to collect data about energy consumption, quantity of environmental emissions and costs. However, most studies on sustainable construction have been concentrated on the use of equipment, maintenance and repair works during construction due to the difficulties of collecting such data. This study suggests a method to select the most environmentally friendly equipment combination for earthwork with comparing environmental loads and costs using the database of Life Cycle Inventory in the Ministry of Knowledge Economy and Ministry of Environment of Korea.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.565-568
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• 2003

Roadway construction planning processes involve a large amount of information on design, construction methods, quantities, unit costs, and production rates. GIS (Geographic Information System) is a strong tool for integration and managing various types of information such as spatial and non-spatial data required for roadway construction planning. This paper proposes a GIS-based system for improving roadway construction planning with its 'Spatial Analysis' and 'Visualization' functions. The proposed system cail help construction planner make a proper decision in a unique way by integrating design information and construction information within the system and creating design element modules for space scheduling purposes in real-time with its 'Interactive Planning' function.

• Journal of Construction Engineering and Project Management
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• v.7 no.2
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• pp.34-44
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• 2017

The use of Unmanned Aircraft Systems (UASs) in the construction and agriculture industries continues to gain in popularity and use. Firms within these industries have begun to utilize UASs to perform many of the traditional processes and procedures, which can result in a reduction in total work force and costs needed for a task. However, as with any technology, there is a learning curve and UASs do change the way certain activities are completed. Due to this, there exist firms and individuals that have not or are not willing to invest in UASs yet. The objective of this study is to explore the applications of UASs in construction and agricultural industries to discuss the benefits, challenges, and reasons of investing in UASs. This paper conducted an in-depth literature review of current topics on UASs in construction and agriculture. Additionally, six expert interviews were conducted with individuals from construction and agricultural industries in the southeastern United States. Ultimately, this study successfully found several benefits and challenges to using UASs and discussed the reasons that some firms invest in UASs while other still do not.

• Journal of the Korea Institute of Building Construction
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• v.13 no.6
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• pp.541-548
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• 2013

During the administration of a construction project, various types of participants are engaged in the project. From the design phase to the maintenance phase, these participants may confront many risks. To avoid these risks, participants should utilize an insurance company or a bond company. The types of risks and liability that a construction manager may face are listed in the construction law or contract. But there are some arguments related to risk transferring and the content of risks. For this reason, construction managers must carefully consider any possible risks in the contract and the construction law. Therefore, for construction managers to deal with risks appropriately, the introduction of a legal requirement to carry professional liability insurance, a defined compensation range for damages, a method of guarantee in the event of defects, a defined compensation claim period for damage, and a method of damage claim were suggested in this study.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.83-91
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• 2004

With labor shortage and high-wage era, the construction cost is rising and the construction business is dull, demanding the construction environment of Korea to raise profitability through major cost savings and rationalization of construction management. However, although reinforcing bar(rebar) work, which greatly effects the building's safety, endurance, and construction time, is an important phase in construction, it holds serious problem of quality and productivity deterioration due to its characteristic of intensive-labor and maintaining of old work methods resulting in poor management, and costs increase. Therefor in this study to investigate current situation and problems of rebar work and to find methods of betterment, a survey was conducted to site engineers and individuals in division of cost estimate of domestic construction company. The survey questions were on the subjects of (1) calculating rebar quantity, (2) ordering and procurement, (3) rebar cutting and bending, and (4) rebar work management. Method of improvement was sought by analyzing the results of the survey

• KIEAE Journal
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• v.10 no.6
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• pp.145-151
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• 2010

Bearing wall system was used extensively in most multi-residential apartment buildings in Korea. However, bearing wall apartments have the lack of architectural plan flexibility, remodelling-incompatible, causing serious economic losses in terms of construction waste. Recently, many researchers have studied the use of Rahmen structure as a potential alternative. The beam-column connection in the paper for long-life apartment housing forms connection of a Rahmen structure utilizing the advantages of steel and reinforced concrete. In addition, reduction of cast-in place concrete and construction schedule is expected by using precast concrete. Reduction effect of quantity decreased construction costs and $CO_2$ emission of key construction materials. However, verifying the feasibility of new construction method entails numerous challenges. Accordingly, the purpose of this study is to analyze the construction feasibility of sleeve, coupler, and pressure welding connections for long-life apartment building structure. A 3D modeling software was used to perform the analysis, and a real scale model was created to verify the results of construction feasibility. By verifying the construction feasibility of beam-column connections, this study will contribute to the efficient application of these methods on construction sites.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.1
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• pp.29-36
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• 2019

In the past, social insurance premiums, such as national pension and national health insurance, is contained within the costs of construction projects, have been lowered due to price competition of companies participating in the bidding. The government is implementing the "Ex-post settlement system" to improve the problem. Therefore, the purpose of this study is to examine the concept of an Ex-post settlement system and background of its introduction and to identify problems in the management of the system. The problems of the Ex-post settlement system are: 1) avoiding the participation of construction workers, 2) the rigidity of the insurance premium settlement method in construction field, and 3) the cause of direct construction cost reduction. The ways to improve these problems are: 1) excluding social insurance premiums from construction project cost, 2) securing flexibility of the settlement method of insurance premiums in construction field, and 3) expanding the scope of persons eligible to participate in social insurance.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.608-615
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• 2022

Construction projects are large-scale projects that require extensive construction costs and resources. Especially, scheduling is considered as one of the essential issues for project success. However, the schedule and resource management are challenging to conduct in high-tech construction projects including complex design of MEP and architectural finishing which has to be constructed within a limited workspace and duration. In order to deal with such a problem, this study suggests resource and sequence optimization using constraint programming in construction projects. The optimization model consists of two modules. The first module is the data structure of the schedule model, which consists of parameters for optimization such as labor, task, workspace, and the work interference rate. The second module is the optimization module, which is for optimizing resources and sequences based on Constraint Programming (CP) methodology. For model validation, actual data of plumbing works were collected from a construction project using a five-minute rate (FMR) method. By comparing actual data and optimized results, this study shows the possibility of reducing the duration of plumbing works in construction projects. This study shows decreased overall project duration by eliminating work interference by optimizing resources and sequences within limited workspaces.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.67-73
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• 2022

Construction bid documents contain various errors or discrepancies giving rise to uncertainties. The errors/discrepancies/ambiguities in the bid document, if not identified and clarified before the bid, may cause dispute and conflict between the contracting parties. Given the fact that bid document is a major resource in estimating construction costs, inaccurate information in bid document can result in over/under estimating. Thus, any questions from bidders related to the errors in the bid document should be clarified by employers before bid submission. This study aims to examine the pre-bid queries, i.e., pre-bid request for information (RFI), from state DoTs of the United States to investigate error types most frequently encountered in bid documents. For the study, around 200 pre-bids RFI were collected from state DoTs and were classified into several error types (e.g., coordination error, errors in drawings). The analysis of the data showed that errors in bill of quantities is the most frequent error in the bid documents followed by errors in drawing. The study findings addressed uncertainty types in construction bid documents that should be checked during a bid process, and, in a broader sense, it will contribute to advancing the construction management body of knowledge by clarifying and classifying bid risk factors at an early stage of construction projects.