• Journal of the Korea Institute of Building Construction
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• v.20 no.1
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• pp.53-60
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• 2020

This paper aims to examine the insulation performance of insulated gang form by changing the energy (power) consumption and concrete calorific value to assist in concrete protection in cold weather. According to the test results, the general gang form will generate three times the energy (power) consumption for 12 hours after the concrete is poured. In contrast, insulated gang foam consumed no energy (power) for 21 hours after pouring. The final power consumption was 3.7 times higher than that of the general gang form, confirming the improved performance of insulated gang form with regard to energy (power) consumption. The calorific value examination shows that the calorific value changes significantly according to the change of outside temperature after concrete placement in the case of the general gang form. However, in the case of the insulated gang form, only a slight heat loss occurred in the part of the frame, and it showed a constant heating pattern from the concrete casting to the demolding of the mold.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.366-375
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• 2007

Our nation has a problem with discrimination of income distribution and inefficient of resources distribution caused by real estate price rising from a sudden economy growth and industrialization. Specially, in recent years, there is a great disparity of condominium price between the north and south of the Han river. Because the housing price is deciede by the immanent value of a house and neighborhood effects of the regional where the house is situated, the housing price is occurred difference. In this study, I analyzed the differences of housing price determinants about condominium developments in the old and new residential areas, and found the important factors that affect the condominium price using Structural Equation Modeling(SEM) The purpose of study is to analyze the influence of various factors of housing price. Also, this study tried to predict real estate market and to establish previous effective real estate policy.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1195-1200
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• 2009

Two important concepts in VE are "function" and "cost." Cost can be expressed quantitatively. Unlike cost, the function can only be expressed qualitatively. Thus, to accurately evaluate the performance in VE analysis, it is required that the functional aspect should be considered a qualitative one. This study suggests a procedure of function oriented evaluation which can evaluate function enhancement of a VE proposal more logically and objectively. To conduct this study, problems were induced via case analysis, and solutions were found. In addition, the existing simple evaluation procedures were corrected, and a function enhancement evaluation procedure via function classification was suggested. For function classification, the use of the concepts, which were "intended function" and "additionally obtained function," was suggested. Function oriented evaluation procedure to VE proposals which is suggested in this study is expected to be a great help in treating valuable functions through VE job plan.

• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.13-21
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• 2016

Insolvency of construction companies that play the role of main contractors can lead to clients' losses due to non-fulfillment of construction contracts, and it can have negative effects on the financial soundness of construction companies and suppliers. The construction industry has the cash flow financial characteristic of receiving a project and getting payment based on the progress of the construction. As such, insolvency during project progress can lead to financial losses, which is why the prediction of construction companies is so important. The prediction of insolvency of Korean construction companies are often made through the KMV model from the KMV (Kealhofer McQuown and Vasicek) Company developed in the U.S. during the early 90s, but this model is insufficient in predicting construction companies because it was developed based on credit risk assessment of general companies and banks. In addition, the predictive performance of KMV value's insolvency probability is continuously being questioned due to lack of number of analyzed companies and data. Therefore, in order to resolve such issues, the Bayesian Probabilistic Approach is to be combined with the existing insolvency predictive probability model. This is because if the Prior Probability of Bayesian statistics can be appropriately predicted, reliable Posterior Probability can be predicted through ensured conditionality on the evidence despite the lack of data. Thus, this study is to measure the Expected Default Frequency (EDF) by utilizing the Bayesian Probabilistic Approach with the existing insolvency predictive probability model and predict the accuracy by comparing the result with the EDF of the existing model.

• Computers and Concrete
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• v.23 no.2
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• pp.145-153
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• 2019

Adaptive schemes are constructed in this paper for modeling the effective chloride diffusion coefficient of cement-based materials (paste and concrete). Based on the polarization approximations for the effective conductivity of isotropic multicomponent materials, we develop some fitting procedures to include more information about the materials, to improve the accuracy of the scheme. The variable reference parameter of the approximation involves a few free scalars, which are determined through the available numerical or experimental values of the macroscopic chloride diffusion coefficient of cement paste or concrete at some volume proportions of the component materials. The various factors that affect the chloride diffusivity of cement-based material (porous material structure, uncertainty of value of the chloride diffusion coefficient in water-saturated pore spaces, etc.) may be accounted to make the predictions more accurate. Illustrations of applications are provided in a number of examples to show the usefulness of the approach.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.491-494
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• 2007

Recently Gas & Oil plant construction projects are increasing in the world. The EPC (Engineering, Procurement and Construction) company, which participate in the plant projects, should possess the pertinent engineering license and procurement skill to create high added-value. It is because the procurement is very substantial to cover 70% of the total project cost. Nonetheless, there exist various risks involved in the procurement process due to the characteristics of the construction projects with long duration and complicated process as well as the procured goods or services subjected to various logistics. The objective of this paper is to analyze proper process in the procurement and to identify various information and document. Also to analyze procurement process, the principal data are derived from the interview with experts and specialty contractors of plant project. The result of this study would widely be used as a guide to the procurement personnel in forecasting the risks in advance.

• Korean Journal of Construction Engineering and Management
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• v.10 no.3
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• pp.13-21
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• 2009

The ideas created by the execution of Value Engineering(VE) during design phase are usually proposed in a scattered way due to the characteristic of brainstorming. Because of this process, it is likely that similar ideas are proposed duplicatedly, and the created similar overlapping ideas may lead to different analyses and evaluations respectively. The efficient analysis/evaluation of the such similarly created ideas are not easy and the verification of the adequacy and objectivity of the ideas becomes harder and the objective evaluation gets more difficult as well as consumes much time. In spite of the perfect executions of preparatory step for idea creation, the difficulties in managing the similarly created ideas in quantity systematically result in the reduced reliability of the VE activities during design phase. Thus, this study proposes a process model for the efficient idea creation and management of the VE activities during design phase.

• Journal of Construction Engineering and Project Management
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• v.2 no.4
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• pp.1-10
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• 2012

Building Information Modeling (BIM) and its different work streams, such as 4D planning (4D), are among the major drivers for change in the construction industry. The primary aim of this research is to create a holistic map of both the barriers and drivers affecting the industrial uptake of BIM and 4D through the use of an extensive literature review and a survey of contractors and consultants from the UK AEC (Architectural, Engineering and Construction) industry. This research demonstrates that while non-technical barriers such as the inefficiency in the evaluation of the business value of BIM and 4D; the shortage of experience within the workforce, and the lack of awareness by stakeholders are recognized by professionals as main barriers to BIM and 4D adoption, current research is still largely concerned with technical advancement of BIM and 4D technologies. A holistic map of the driving and restraining forces affecting BIM and 4D widespread adoption was provided. The tackling of the non-technical barriers identified will help bridge the gap between technology, end-users and their processes.

• Journal of the Korea Institute of Building Construction
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• v.13 no.2
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• pp.112-121
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• 2013

Korean overseas construction has been on the rise, and exceeded the 2011 goal of $50 billion by securing $59.1 billion in orders. However, these orders were heavily concentrated in the Middle East (50%) and plant construction contracts (75%). This study suggests that, to maintain growth in foreign markets, Korea construction companies should enter into the high value-added investment development business and aggressively seek ways to diversify their regions of activity and construction types. To secure the entry of Korean construction companies into lucrative markets and better understand the competitive factors facing Korean construction concerns, a survey of the literature and focus group discussions targeting relevant experts were carried out. From those efforts, a list of 44 competitive factors crucial to entering and competing in the international investment development business was developed. Survey responses were analyzed by applying IPA. The results revealed that while Korean concerns compete well in engineering/technical capabilities, maintaining a cooperative relationship with contractors, and warranty/after sales service capabilities, their ability to obtain business information on the target country, to form private/public cooperative systems, and to build international human networks require immediate improvement.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.46-53
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• 2015

Electrical construction cost index is composed of the cost of albor and material. The producer price index is used to the cost of material. The Bank of Korea restructured the formation method and the basic period of the producer price index in 2013. Because fixed-weighted method can't faithfully reflect industrial structure changes. The weighted value and price index of fixed-weighted method is fixed on the basicp eriod. Electrical construction cost index is changed from fixed-weighted method to chain-weighted method in september 2014, because of these on the need. But the change of organization in formation method changes the weighted value. So there is the need of analysis about the statistical continuity of electrical construction cost index. This study is focused on the time series analysis between fixed-weighted and chain-weighted electrical construction cost index. We uses unit root test, cointegration test, regression analysis of long and short term equation, fitness for the estimation of static forecast as time series analysis. We verify that chain-weighted electrical construction cost index can be replaced to fixed-weighted construction cost index accounting analyses result. So users of it recognize that chain-weighted electrical construction cost index has statistical continuity.