• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.506-514
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• 2014

Recently the interest about the vortex intakes are rapidly increased because of its performance to drain a plenty of collected storm water at a time. The tangential intake a kind of vortex intakes is very applicable because this type is very simple and little against other types, but it has a big weakness that the vortex flow is not been rarely created below the design discharge. In this study, the characteristics of a tangential intake and two kinds of a newly suggested compound section type intake are analyzed by the 3D numerical modeling based on theories about the control shift and free drainage condition. The analysis focused on the flow condition, flow surface formation, depth-discharge relation, area ratio of air core. Based on this study, the mild-sloped compound section type intake is the optimal, but steep-sloped compound section type is also the optional for the small design discharge.

• Korean Journal of Construction Engineering and Management
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• v.15 no.1
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• pp.3-10
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• 2014

High-rise buildings need thorough cost management because of large size and high risk. Cost management makes a budget by establishing and analyzing detail element at planning phase, needs cost control as each design phase, then reflected to next design. This research develops a schematic estimation model based on vertical and horizontal elements at design phase for structure cost of high-rise buildings to reduce error range and use data as design management. Usability of the model is confirmed by case study. The estimation model is expected to contribute to making the cost model more effective and satisfactory to concerned in construction or budget department and manage keeping track of the cost.

• Journal of Drive and Control
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• v.17 no.2
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• pp.1-8
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• 2020

Recently, industrial systems are becoming quicker and lighter to enable the reduction of energy consumption and increase productivity. So the latest systems are more flexible and rapid than the previous systems. But, with this improvement, another problem has emerged, such as the increase in residual vibration when a system is started or stopped. The input shaper is a command generation method that can remove residual vibration. It can provide a solution to the problem of residual vibration in industrial systems. However, it is difficult to generate the input shaper in high order systems, such as a typical industrial system because the input shaper is induced from the system's vibration characteristics. This study focused on the extra insensitivity shaper that can compensate for the system's modeling error such as input dynamics, and the high order's system affection. A genetic algorithm was deployed to adjust a vibration limitation for the extra insensitivity of the input shaper. A plant is a low damping system that includes one zero and a pole. The fitness functions are an error signal of the system's response with normalized frequency variations. Verification of the suggested system is satisfied by comparison between the zero vibration derivative input shaper's response and the suggested one.

• Journal of the Korean Society of Safety
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• v.35 no.3
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• pp.43-48
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• 2020

It is considered that most of reusable pipe supports, which are used as formwork support posting at construction sites, do not meet the performance standard. Due to the use of reusable pipe supports that do not meet such performance standard the potential risk of collapse accident is increasing. Therefore, this study identifies the status of compliance with performance standard, and presents the requirements for improving quality control to prevent the collapse of pipe supports reused at the construction site. First, if the female thread of the product with no clearance and new support pin with the diameter of 12mm are replaced at the same time for use, it is considered that the performance will be improved. Second, as the quality performance during use can be improved in the case of larger thickness of inner diameter compared to the case of larger thickness of outer diameter, it is necessary to increase the inner pipe thickness greatly than the current thickness. Based on the results of this study, it is expected that the performance the reusable pipe support (V4) can be improved, if the diameter of the support pin is 12mm, the female thread has a small clearance, and the inner tube thickness is 2.3 ~ 2.7mm. In addition, it is considered that other performance improvement factors included in the study results could be used as important data for improving the performance of reusable pipe support.

• Korean Journal of Construction Engineering and Management
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• v.21 no.2
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• pp.30-38
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• 2020

Inadequate cost management has widely been recognized as one of the most problematic areas in the Korean construction industry as many believes that public cost references are not reasonably reflecting the market conditions. 'Total Project Cost Management Guideline' developed by Ministry of Economy and Finance(MOEF) to govern public budget control has been identified as one of the main reasons for this problem. This study attempts to thoroughly review 'Total Project Cost Management Guideline' itself and quantitatively analyze the impact of it on project cost during procurement process. Different procurement methods are considered including turnkey & alternative, private contract, qualification examination, and lowest price bidding system in this quantitative impact analysis of 'Total Project Cost Management Guideline'. Analysis results shows that this governmental process works mainly as a constant cost-cutting tool throughout the procurement process.

• Journal of the Korean GEO-environmental Society
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• v.5 no.3
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• pp.5-15
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• 2004

SIP has been widely used as a low noise and vibration piling method in Korea. But the quality control of SIP was not properly settled down and field workers did not fully understand the principle of SIP method. So not a less troubles were raised at construction site and bearing capacity was not fully mobilized. To settle these problems, Korea National Housing Corporation amended the construction and load test criteria of SIP in 2002. After load tests on the SIPs installed in field according to the new criteria, we found that the bearing capacity in field vs the design load ratio increased and bearing characteristics was enhanced than that installed by the former criteria. To consider the enhanced bearing characteristics in the pile design and determine the adequate design criteria, this paper analyzed the accuracy of design criterion which were commonly used in Korea comparing with the load test results. Analysis result shows that Meyerhof criteria(1976) properly simulates the bearing capacity of SIP installed by the new construction and load test criteria.

• Korean Journal of Construction Engineering and Management
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• v.8 no.1 s.35
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• pp.116-123
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• 2007

Recently orders of project in the field of oil & gas plant have been increased due to raising oil prices and consumptions. Domestic oil & gas companies are expanding into the Middle East area and all over the world. In the field of oil & gas plant, it is important to manage a technical control and a license that is occurred when developing the manufacturing processes and technologies. Because the oil & gas market has a lot of executions of the oversea construction, competitions between the advanced companies is more important. Therefore, we have to adopt systematic management style for achievements of the technical competitive power and the higher position. However, domestic oil & gas plant companies have not enough competitive powers of the license and the design phase. So, they are faced with difficulties of adopting the technology which is maximizing the effect of investments and scheduling a long-range plan. To achieve the technology management and the competitive power, this study proposes a long-range plan through the analysis of execution methods for technology management.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.148-152
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• 2007

In recent days, on account of the cultural development and the improvement of citizen's consciousness level, it is the real situation that the construction of small-scaled Multi-Purpose Hall where various cultural events could be performed, is on increasing. However, since the most of Multi-Purpose Hall had been designed and built up without any consideration on Acoustic Factor, many problems are on occurring thereat. Since those small-scaled Multi-Purpose Hall have been mostly used with the finishing material which contains a high degree of Acoustic Absorption indiscreetly, both diffusion and reflection of sound are not establishing properly, and because thereverberation of sound is very low, in case of musical performance by musical instrument, its sound hears too arid and stiff, there occurs some acoustic defect such as it becomes difficult for music appreciation with sufficient timbre, so that the capability improvement on the matter is urgently requiring situation. Therefore, this Study has tried to seize the satisfaction level about the small-scaled Multi-Purpose Hall after betterment of the acoustic performance by appraise the acoustic condition of the Hall, using Auralization Technique that can experience Virtual Acoustic Field regarding to the small-scaled Multi-Purpose Hall as its object. It is deemed that such research result could be practically used as the useful material which enables to bring a reduction effect of construction cost as well asenhancement of the acoustic performance through its presupposition?control on the acoustic problem when construction or renovation of other similar small-scaled Multi-Purpose Hall in the future.

• Journal of Korea Water Resources Association
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• v.45 no.10
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• pp.1009-1022
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• 2012

This study approach the conflict in the process of promoting Dam construction plan from a hydrological method and comprehend the cause of conflict on conservation and flood collect all interested parties direct involvement and develop Shared Vision Model (SVM) to plan simulation and result. We forecast water for living, industrial water and agricultural water in each administrative district on conservation and simulate promptly in case that each structural alternative is formed and suggest water level deduction effect and change of area on watted surface and damage and organize the system to draw and agreement through exchanging mutual opinion. Also, it considered to contribute meditation and soften of conflict by securing accuracy of releasing information and trust of the result.

• Journal of the Korea Convergence Society
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• v.8 no.8
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• pp.59-69
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• 2017

Humanities and social sciences researchers and database experts have teamed up to build a database of IPR materials prepared by the Institute of Pacific Relations (IPR). This paper presents the issues and solutions inherent in the database construction for ensuring the quality of IPR materials. For the accessibility of the database, we maintain the database on the Web so that researchers can access it via web browsers; for the convenience of the database construction, we provide an integrated interface that allows researchers to perform all tasks in it; for the completeness of IPR materials constructed, we support the responsible input and the responsible approval that identify responsibilities of each IPR material entered; and for the immediacy of the approval, we support an interactive approval process facilitating the input of researchers. We also use database design, query processing, transaction management, and search and sorting techniques to ensure the correctness of IPR materials entered. In particular, through concurrency control using existence dependency relationships between records, we ensure the correctness between the operating system files and their paths. Our future studies include content search, database download and upload, and copyright related work on IPR materials.