• Proceedings of the SAREK Conference
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• 2004.11a
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• pp.4-4
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• 2004

• Journal of the Korean Operations Research and Management Science Society
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• v.20 no.2
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• pp.77-93
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• 1995

A mathematical model for long-rage water supply planning was formulated as a dynamic plant location problem with network arc capacity expansion, and illustative example was presented. The proposed solution procedure identifies economical construction timings of surface water supply facilities and water conveyence systems and the best water supply operating patterns as well. In this study, we present a heuristic solution procedure using Simulated annealing Method in conjunction with Bertsekas & Tseng's RELAXT-II for the 0-1 integer network problem.

• Proceedings of the KIEE Conference
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• 2007.04b
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• pp.152-154
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• 2007

This paper represents the criteria of earthing system for substation design in Korea. The construction of new substations and expansion of existing facilities are commonplace projects in KEPCO(Korea Electric Power Corporation). The KEPCO has had the only design criteria, which need to be adequate criteria considering the new technology and environment in Korea.

• Kyungpook Mathematical Journal
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• v.61 no.2
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• pp.269-278
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• 2021

In this paper, we investigate harmonic univalent functions convex in the direction 𝜃, for 𝜃 ∈ [0, 𝜋). We find bounds for |f_z(z)|, ${\mid}f_{\bar{z}}(z){\mid}$ and |f(z)|, as well as coefficient bounds on the series expansion of functions convex in a given direction.

• Korean Journal of Construction Engineering and Management
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• v.10 no.5
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• pp.135-147
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• 2009

The world has witnessed the dramatic expansion of international construction markets during the last decades, particularly around the developing economies and energy resource-rich countries. However, despite the booming markets, the risks of emerging regions have also increased under the rapidly changing environments confronting the global contractors. Most of all, success in overseas business mainly depends on selecting the right market to enter. Accordingly, the right market selection requires global firms to carefully carry out the scientific market entry decision by evaluating country risks, market prospects, firm's capability, level of competition, and among others. This study aims at developing a market entry model by the use of real option analysis (ROA) and scenario planning, which addresses the corporate strategic flexibility against the uncertainties encompassing the overseas construction markets. Based on the suggested approach, global contractors are expected to make a better decision rather than a typically static approach in pursuing, postponing, or abandoning a prospective market to their capacity with a concurrent consideration of uncertainties as well as its option value.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.995-998
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• 2007

The number of households old over as much as 20 years is expected to get increased rapidly more than 1,000,000(1 million). As a measure to this fact remodeling is being revitalized over the country. parking lots expansion actually takes up a great deal of weight among the requirement for remodeling. When constructing a parking lot for enlargement, the way of going into the main building determines such construction features as selection of Retaining Wall Method, installation of an elevator, parking measure of capacity, etc. This study derived the affecting factors for selecting the way of going into the main building when constructing an underground parking lot. In a research way, we examined the features on each method of going into the main building in an apartment complex through an in-depth interview with some experts after investigating the method of enlarging an underground parking lot and going into the main building. After that, we derived the affecting factors for selecting the way of going into the main building. The affecting factors include constructability, convenience, economic efficiency as a high level as well as existence and nonexistence of basement and removal, safety of current building, parking measure of capacity, amenity, inhabitant traffic line, construction expenses and construction duration as a low one. This study will be applied as a reference for selecting the way of going into the main building when constructing an underground parking lot especially targetted on an old apartment house.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.99-103
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• 2003

The most commonly used method for space management in the industry is development of site plans. These plans outline how to manage material deliveries, staging areas, and crane locations for construction sites in suburban area but not in congested urban areas. This study focuses on how to efficiently manage space for construction facilities on high-rise buildings in congested urban areas where normally space for facilities around a building footprint is not available. The limitations of available horizontal space create a need to explore vertical expansion of facilities. This raises new aspects of vertical facility handling and flow that need to be considered in the facility design problem. The construction facilities layout plan method provides layout planners with a valuable technique to develop efficient sequences of work that optimally defines how to efficiently utilize the construction facilities and minimize the travel of specific facilities effort on multiple-floor buildings. A genetic algorithm-based heuristic will be presented for generating block layouts for multiple-floor la)rout problems.

• Journal of the Korean Society for Advanced Composite Structures
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• v.5 no.2
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• pp.21-26
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• 2014

This paper introduces general concepts of jointless bridges and field construction case of semi-integral bridge with psc girder integrating end-diaphragm. The expansion joints need to satisfy thermal and safety conditions of bridges. General bridges with joints have some problems, which are frequently replacement cycle time from mechanical damage or unstable movement, maintenance cost and more. To solve these problems, Integral Abutment Bridges(IAB) have been applied overseas in the 1930s. In Korea, first IAB was constructed in the early 2000s and precast IAB systems was invented and applied lately. Kyungshin overpass bridge in Incheon is the Semi-IAB constructed, the span length is 2@35=70m and the width is 13.9m. The original plan was to use general joint bridge but design field changed with expectations for advanced economic estimation and maintenance. This changed method of B.I.B bridge construction provided not only workability, construction cost but also safety improvement at the same time.

• Land and Housing Review
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• v.11 no.3
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• pp.11-19
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• 2020

This study aims to examine the relationship between the improvement of the income distribution index from the late 1980s to the 1990s and large-scale housing supply projects such as the 2 million housing construction project. Looking at Korea's economic development in terms of income growth and distribution, GDP has continuously increased since the establishment of the government, especially in the late 1980s. The Gini Index, a representative income inequality index, rapidly deteriorated in the early 1970s, and gradually improved from the late 1980s. The 2 million housing construction project, announced in 1988, supplied a third of the existing nationwide housing stock of 6.5 million units in three years. The project cost was 65 trillion won, equivalent to 50% of Korea's GDP at the time. This study questioned whether the ratio of the number of employed workers in the construction industry was a variable directly affecting the Gini Index. To verify this, the causal relationship between the proportion of employed workers in the construction and manufacturing industries and the Gini Index from 1979 to 2008 was statistically analyzed. For this, the ARIMA model was established for each variable, and the correlation of their residuals was verified. The 2 million housing construction project had the effect of improving income inequality in terms of rising wages for production workers and creating jobs for the low-educated and low-income class. During the project period, the number of middle-income earners increased sharply, and the income gap between the high-income and low-income earners greatly decreased. The expansion of the construction volume can be used as a powerful and direct policy tool for improving income distribution. However, the effect may be limited. When the proportion of workers exceeds the threshold, the effect is weakened.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.392-395
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• 2007

Recently, the construction wastes rapidly increase because of redevelopment, the development of new urbanization of large housing development, the expansion of social infrastructure. With increase of the construction noise caused by these developments, environmental conflicts and civil appeals increase. Moreover, the Government will reduce construction noise level to 65dB from 70dB in January 2009. Therefore, it will be expected to increase environmental conflicts and civil appels related to construction noise. To minimize environmental conflicts and civil appels, this study compared and analyzed measured noisy values of a crusher for the site-recycling to predicted value of simple noisy prediction program developed by "National Institute of Environmental Research". Based on the results, a crusher for the site-recycling can be arranged to minimize the noise.