• Magazine of korean Tunnelling and Underground Space Association
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• v.21 no.2
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• pp.103-116
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• 2019

Permanent sprayed concrete tunnel linings waterproofed with bonded membranes have been used at a number of important traffic projects over the last decade. Research has been carried out in several teams in order to increase the understanding of the function, properties and behavior of such linings under different loading and boundary conditions. The basic layout of this lining gives fundamental different system properties compared to the traditional lining systems. The main differences pertain to the groundwater exposure and the resulting hydraulic loading, the response of the concrete and membrane materials to this loading, as well as the geomechanically induced loading of the lining structure. The current understanding of the function and properties of such lining structures is presented in the paper based on review of recent research carried out in Norway, as well as field observations and monitoring carried over a several years. The influence of the water exposure on the final condition of the concrete and membrane materials has proven to be of vital importance for proper material testing and acceptance, assessments of the mechanical contribution of the bonded membrane, as well as assessments of the longterm durability of such linings. Obtaining realistic material parameters for the concrete and membrane materials subject to the boundary conditions posed by the groundwater exposure in an undrained structure is emphasized. Finally, some recent results from currently ongoing research on such linings, particularly the hydraulic response of the rock mass and the long term behavior of the concrete and membrane materials are presented.

• Journal of the Korea Society of Computer and Information
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• v.21 no.5
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• pp.161-166
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• 2016

This paper suggests heuristic algorithm with O(m) linear time complexity for choice of expansion projects that can't be obtain the optimal solution using linear programming until now. This algorithm ascending sort of net profit for all projects. Then, we apply a simple method that deletes the project with minimum net profit until this result satisfies the carried over for n-years more than zero value. While this algorithm using simple rule, not the linear programing fails but the proposed algorithm can be get the optimal solution for experimental data.

• Journal of Fashion Business
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• v.15 no.1
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• pp.20-33
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• 2011

The purpose of this study is to inquire into social and cultural background of modernization and the new woman's life centered around a new woman and a dancer, Choi Seung-hee and its style. The study was carried out centered around analysis of content through photos of 179 pieces and a documentary DVD. We analyzed collected photo data and came to know various bobbed hair style, clear makeup style and Art-Deco fashion. Accordingly, Choi Seung-hee has external appearance as a new woman and we came to know she is a representative woman in Korea. Because she crossed over into North Korea, the study has not been actively carried out but if we consider Choi Seung-hee's influence over the dance world, her women's leader and fashion roles at that age, it is considered that the study on Choi Seung-hee's external style has a significant meaning.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.622-625
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• 2008

While the research for flow over a circular cylinder has been actively carried out up to the present, it has been known that the flow has not been clarified even now. Various complex flow and aero-acoustic characteristics exist around a circular cylinder such as flow separation, wake and pressure wave propagation. In this paper, research was carried out for wake flow and aeroacoustics over a circular cylinders by using high order, high resolution techniques that are used in two dimensional aero- acoustic analysis. OpenMP parallel processing method was used. For the numerical result, the periodic characteristic of Strouhal Number due to vortex shedding was comparatively analyzed with other experiment values and two dimensional numerical results.

• Proceedings of the KSR Conference
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• 1999.05a
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• pp.442-449
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• 1999

Due to temperature variations, considerable longitudinal rail forces and displacements may develop in continuous welded rail(CWR) track on long-span bridges or viaducts. Excessive relative displacements between sleepers and ballast bed may disturb the stable position of the track in the ballast which results in a lower frictional resistance. Generally, these problems are solved by installing rail expansion devices. However the application of expansion devices in high-speed tracks on existing bridges, as a means to prevent excessive longitudinal displacements and forces, is not attractive method due to comfort, safety and maintenance aspects. An alternative and very effective solution is possibly the use of so-called zero longitudinal restraint(ZLR) fastenings over some length of the track. The calculations, carried out in this respect, show a considerable reduction of track displacements, track forces, and the relative sleeper/ballast displacements. This reduction depends on the length over which these fastenings are installed. In this paper calculations of the longitudinal displacments and forces in a CWR track and substructure resulting from thermal, mechanical and kinematical loads were carried out using the FEM analysis program LUSAS

• Journal of Ocean Engineering and Technology
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• v.18 no.2
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• pp.52-57
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• 2004

Preflex beam is a method of construction designed to hold the pre-compressive stresses over the concrete pier by the preflexion load. During the fabrication of the girder, welding causes residual stresses. The welding residual stresses must be relieved in order to generate the accurate compressive pre-stresses. In this study, to determine the thermal distribution characteristics on the girder by welding, both three-dimensional finite element analysis and two-dimensional finite element analysis, in a quasi-steady state, is carried out. After comparing each result between the three-dimensional analysis and the two-dimensional analysis, finite element analysis is carried out against the actual girder, and the welding thermal distribution characteristic over the preflex beam is analyzed. It is possible to provide the input data for the analysis of the welding residual stresses.

• Journal of Korea Multimedia Society
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• v.22 no.9
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• pp.983-991
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• 2019

Histogram equalization method is a popular contrast enhancement technique. However, there are some drawbacks, namely, over-enhancement, under-enhancement, structure information loss, and noise amplification. In this paper, we propose an edge-enhancing histogram equalization algorithm while suppressing over-enhancement simultaneously. Firstly, over-enhancement is suppressed by clipping a transfer function, then, edge enhancement is achieved by using guided image filter. Experiments are carried out to evaluate the performance of the various HE algorithms. As a result, both qualitative and quantitative assessment showed that the proposed algorithm successfully suppressed over-enhancement while enhancing edges.

• International Journal of Highway Engineering
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• v.15 no.3
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• pp.169-176
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• 2013

PURPOSES : Lots of criticism such as over/duplication investment, inconsistency of the policies among local governments and national plans etc. has been aroused due to the policy of supply-driven construction for transportation facilities. Recently, according to the environmental-friendly transportation policy, the investment of railroad has been expanded gradually, however the duplication with existing road facility makes it difficult to construct railroad. Thus it is necessary to evaluate the interrelationship between new project and existing facilities in the planning stage. However the method and the criteria for analyzing the duplication and over-investment of projects are not established in the manual, thus the feasibility of these projects are carried out from the economic point of view. METHODS: First, It reviewed about interrelationship criteria(domestic, overseas) and proposed implications and this study directions. Next, It developed the methods of evaluating independency, competitiveness and complementarity. RESULTS : In this study, the methods of evaluating independency, competitiveness and complementarity etc. are suggested to analyze the interrelationship between transportation facilities. The case study was carried out to examine the applicability of the methods. CONCLUSIONS: The methods raise rationality of decision-making compared to existing one. In the future, these methods are introduced into the manual of pre-feasibility study and feasibility study, more efficient decision-making and investment are expected.

• Journal of Agricultural Extension & Community Development
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• v.13 no.2
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• pp.329-340
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• 2006

This study was carried out to analyze on the economic life and financial state of rural inhabitants in case study 4 villages by questionnaire interview. To analyze the economic life of rural inhabitants, the data were collected from 191households and the SPSSWIN / ver12.0 was used for analyzing them. The major findings of this study are as follows; 1) Most of them earned living expenditure themselves, over 15% inhabitants lived with their children supports. 2) Over 70% of them couldn't save at all, over 40% of them had debts except inhabitants in plain area. 3) The financial condition of rural inhabitants is very unstable, for the small and irregular agricultural income. Moreover, the ratio of national pensioner and payer are very low. 4) The present economic life compared with 10year ago and future prospect are pessimistic. And the elder household have much financial problems, they live in poor and inferior surroundings. According to the results of research, the policy on support and assistance for economic life of rural inhabitants must be enlarged and enforced, and the financial program and education for them must be carried out nationwide and systematically.

• Wind and Structures
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• v.32 no.2
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• pp.115-126
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• 2021

The snow cornice mass on the formation zone had triggered avalanches which led to the loss of human life and property. Snow cornice is formed due to flow separation on the leeward side. Effect of lee slope is more prominent in the formation of snow cornices as compared to the windward slope. The analysis of wind flow pattern has been carried out to evaluate the performance of a jet roof. Computational Fluid Dynamics (CFD) analysis of wind flow over a 2D hill model was carried out using RNG based k-∈ turbulence models available in ANSYS Fluent. Effect of varying leeward hill slope (1:2 to 1:6) on flow separation for the given windward slope was observed and a critical slope of 1:4 was found at which the separation zone ceased to exist. The modification of wind flow over a hill due to the installation of jet roof was simulated. It was observed that jet roof had significantly modified the wind flow pattern around hill ridgeline and ultimately snow cornice formation had mitigated. The results of the wind flow pattern were validated with the wind data collected at the experimental site, Banihal Top (Jammu and Kashmir, India). The wind flow simulation over the hill and mitigation of cornice formation by the jet roof has been explained in the present paper.