• Wind and Structures
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• v.26 no.4
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• pp.191-204
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• 2018

This article presents a study of the largest-ever (height = 220 m) cooling tower using the large eddy simulation (LES) method. Information about fluid fields around the tower and 3D aerodynamic time history in full construction process were obtained, and the wind pressure distribution along the entire tower predicted by the developed model was compared with standard curves and measured curves to validate the effectiveness of the simulating method. Based on that, average wind pressure distribution and characteristics of fluid fields in the construction process of ultra-large cooling tower were investigated. The characteristics of fluid fields in full construction process and their working principles were investigated based on wind speeds and vorticities under different construction conditions. Then, time domain characteristics of ultra-large cooling towers in full construction process, including fluctuating wind loads, extreme wind loads, lift and drag coefficients, and relationship of measuring points, were studied and fitting formula of extreme wind load as a function of height was developed based on the nonlinear least square method. Additionally, the frequency domain characteristics of wind loads on the constructing tower, including wind pressure power spectrum at typical measuring points, lift and drag power spectrum, circumferential correlations between typical measuring points, and vertical correlations of lift coefficient and drag coefficient, were analyzed. The results revealed that the random characteristics of fluctuating wind loads, as well as corresponding extreme wind pressure and power spectra curves, varied significantly and in real time with the height of the constructing tower. This study provides references for design of wind loads during construction period of ultra-large cooling towers.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1168-1173
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• 2004

Bridges and tunnels mainly compose the structural system of Kyung-bu high-speed railway in Korea and the prestressed concrete box girder bridges are applied for the most part of bridge structures. Precast full span construction method was practiced in the construction of many prestressed concrete box girder bridges in Kyung-bu high speed railway for the high quality, great construction speed, low construction cost and construction safety. However, there have been no application of this method in continuous bridges until now. Therefore, a new advanced precast full span construction method is developed using pre-tensioning for precast and post-tensioning in alternating the simple span into a continuous bridge system. since the high-speed railway trains can cause dynamic problems in a continuous bridge. This study shows the structural behavior and the construction process of the new advance method.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1081-1087
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• 2009

An automatic construction system in Korea is now at the stage of the full automation like in Japan, and an actual pilot project is going to be built in 2009. However, in developing a new construction system that has never been implemented before, there is a need to assess the performance and to consider the uncertainty of the system. The program evaluation and review technique (PERT) allows dealing with this uncertainty. Thus, this paper implements an analysis of the process of steel fabrication and makes suggestions for time-related problems arising from the analysis. The time required for steel erection by the automatic system was compared with that in the traditional method. In the result, finding out another construction process and improving robot performance were proposed to resolve the problems. The results will contribute to promoting the development of an efficient system for the new automatic construction system.

• Journal of the Korea Institute of Building Construction
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• v.7 no.3
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• pp.91-98
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• 2007

Recently a construction industry introduces information that brings about many advantages in the early planning phase, design phase and construction phase. Especially it replaces 2D, 3D systems(usually using explanation of drawing information) ai 4D CAD(offering a sort of 4D-having relation of construction schedule and 3D drawing information). Nevertheless a 4D has these benefits, it has limits which are not only usually using 3D modeling but also limit of making full use of practical affairs because of a lack of connecting varietals of progress of work. To solve these uppermost limits, this research is presenting unified systems to use in risk management which are efficient management of space and non-space information, space analysis, making full use of data base, introducing GIS system of easy interaction.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.781-787
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• 2009

Training and process analysis in the construction industry has not taken full advantage of new technologies such as building information modeling(BIM). The purpose of this research is to develop a framework for the virtual interactive construction education system using three dimensional technologies. The modules will simulate the construction process for a facility from start to finish using information drawn from real projects in the built environment. These modules can be used as training tools for new employees where they attempt to optimize time and cost in a virtual environment given a limited number of equipment, time and employee options. They can also be used as a process analysis tool for new construction where a number of situational variables can change leading to exposure of potential risk. These modules would be particularly useful for repetitive construction where the initial project is analyzed for optimization and risk mitigation. This paper describes the framework and shows a residential construction example using a 900 square foot wood frame single family house designed for the United States.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1075-1080
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• 2003

Design and fabrication process of a full inorganic electroluminescent microdislay based on aluminum / nanostructured porous silicon reverse biased light emitting Schottky diodes are discussing. Being of a solid state construction. this micro-display is cost-effective, thin and light in weight due to very simple device architecture. Its benefits include also super high resolution, wide viewing angles, fast response time and wide operating temperature range. The advantages of full integration of a LED-array and driving circuitry onto a Si-chip will be also discussed.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.145-150
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• 2013

As a recent global trend, the majority of mega-size plant projects are delivered through EPC (Engineering, Procurement and Construction) contracts, where a single contract is awarded for engineering, procurement, and construction. Under this contracting mechanism, it is challenging for contractors to carry out the projects under traditional project management processes used in design-bid-build projects. A new EPC Plant, the POSCO Special Steel Plant in Changwon, was built successfully at the beginning of 2012 and it is currently in full-scale production. The project has encountered a number of major difficulties however, with some technical and managerial issues through its development process. As summarized in this paper, the authors (as project participants with the contractor) investigated it as a post construction analysis and recorded the Lessons-learned for future project management improvement.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.3
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• pp.195-209
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• 2013

Purpose of this study is to empirically consider relation between QM activity factor and management result. For this, following 6 major variables of QM activity were established as independent variable; CEO's leadership, communication, process control, standardization, full participation and education/training while satisfaction of members and improvement of quality were established as dependent variable. And, a model was set up and hypothesis verification was conducted on the basis of data collected through questionnaires. The results are summarized as follows; First, QM factors which influenced satisfaction of members in management result were CEO's leadership, communication, process control, full participation and education/training but 'standardization' factor was not statistically significant. Second, QM factors which influenced improvement of quality in management result were CEO's leadership, communication, standardization, full participation and education/training but 'process control' factor was not statistically significant. Third, among main factors of QM activity, the factor which preferentially influenced satisfaction of members was 'full participation' factor while the factor which preferentially influenced improvement of quality was 'standardization' factor. According to such results, it is required to seek a statistical method regarding QM activity with focus on the factor of 'full participation' and 'standardization' among other things for the purpose of satisfaction of members as well as improvement of quality. It is believed that implication of this study can be useful information to realize management result considering main factors of QM activity and that it also can be basic reference data to seek a statistical method for satisfaction of members and improvement of quality by grasping core factors having influence over QM activity.

• International conference on construction engineering and project management
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• 2007.03a
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• pp.450-458
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• 2007

This paper presents the results of a statistical analysis and its research findings focusing on the learning aspect in the process of international joint ventures (IJVs). The contents of this paper is derived from a sample of 96 field cases based on a proposed conceptual model of effective learning for international construction joint ventures (ICJVs). The paper presents a brief review on the conceptual model with hypotheses and summarized the key results of statistical analysis including factor and multiple regression analysis for the testing of the validity of the proposed conceptual model and its associated research hypotheses. Among other research findings, the research confirms that ICJVs provides an excellent platform of in-action learning for construction organization and suggests that good outcomes in learning could be reaped by a company who has a clear learning intent from the beginning and subsequently take corresponding learning actions during the full process of the joint venture.

• Journal of The Korean Digital Architecture Interior Association
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• v.6 no.2
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• pp.9-16
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• 2006

The research want to know about form creation method's special quality that found in digital construction design process that using digital media, and they comparison analysis that who positive using digital media, Frank O. Gehry, Peter Eisenman, Greg Lynn, UN studio's work. First, In digital design process using digital media is make full use to design unfolding step and application way can change by architect's recognition difference of using digital media and each architect's design general idea unfolding process, and it means form creation process can change. Second, In digital design process a building form doesn't design adaptation to construction system, they directly design the third dimension form. So, they deduction a new form that unification and integration. Third, the architect that appear's in digital design process's part is existing, data from position of the master which it selects the coding selects the outcome goods which appears in computer operation with coordinator role of the originality and construction sense which it is visible.