• Structural Engineering and Mechanics
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• v.56 no.6
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• pp.983-1001
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• 2015

This study focuses on the load carrying capacity and the force transfer mechanism of multi-hole perfobond shear connectors in steel-concrete composite structure. The behavior of multi-hole perfobond shear connector is more complicated than single-hole connector cases. 2 groups push-out tests were conducted. Based on the test results, behavior of the connection was analyzed and the failure mechanism was identified. Simplified iterative method and analytic solution were proposed based on force equilibrium for analyzing multi-hole perfobond shear connector performance. Finally, the sensitivity of design parameters of multi-hole perfobond shear connector was investigated. The results of this research showed that shear force distribution curve of multi-hole perfobond shear connector is near catenary. Shear forces distribution were determined by stiffness ratio of steel to concrete member, stiffness ratio of shear connector to steel member, and number of row. Efficiency coefficient was proposed to should be taking into account in different limit state.

• Journal of Distribution Science
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• v.16 no.1
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• pp.37-46
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• 2018

Purpose - This study is to investigate the effects of consumption motives of restaurant customers on the perception of the importance of restaurant attributes, and to determine the influence of the consumption motives on the empirical and functional attributes between Vietnam and Korea. Research design, data, and methodology - Questionnaire items from previous studies were revised to fit the research purpose of the present study. From August 1 to August 25, 2017, questionnaires were simultaneously administered in Korea and Vietnam using both on-line and off-line survey methods (including SNS and e-mail). With 381 surveyed questionnaires in Vietnam(219) and Korea(162), this study was conducted by using SPSS 22.0 to verify the reliability and validity of the measured variables. Structural equation model (SEM) was employed as a statistical method for the hypotheses test of this study. Results - The results showed that hedonic eating-out motive has more influence on the importance of empirical attribute than that of functional attribute in restaurant. In addition, utilitarian eating-out motive has more influence on functional attributes than empirical attributes. However, these relationships showed the difference between countries in Vietnam and Korea. As for in Korea, consumers' hedonic and utilitarian motives of eating-out were more influential on experimental and functional attributes. Conclusions - This study analyzed the influence on the importance of the eating-out motives of restaurant attributes and how this differed between Vietnamese and Korean.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.2
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• pp.73-79
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• 1999

Most of mechanical structures are combined of substructures such as beams and/or plates. There are few systems with unibody structures but are many systems with united body structures. Generally the dynamic a nalysis of whole structures is performed under alternation load. In the structure design, the analysis of each bolted joint is more important than others for zero severity. This paper presents the analysis method of contact stress distribution factor in the bolted joint with variable fastening torque on joints in the structure. At first, a static vibration test was performed to find out a nominal stress of bolt jointed plates from the relationship between natural frequency and nominal stress. Then a contact stress was computed at contact point between bolt and plate in the structure. It is believed that the proposed method has promisiong implications for safer design with index of contact stress distribution factor and has merits for cost-down and saving time at the beginning of vehicle development.

• The Korean Journal of Ecology
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• v.25 no.1
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• pp.51-58
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• 2002

An investigation of occurrence and distribution of dictyostelid cellular slime molds in South Korea were carried out. Thirty-one dictyostelid cellular slime molds were isolated from soils of 256 sample sites of 41 area within mountain forests, riversides, streamsides and coastal area in South Korea. The average number of species isolated at a given study area was 6.85. Based on the distribution value calculated from average frequency and site presence, four dictyostelid species distributed widely in South Korea; Polyspondylium pallidum, P violaceum, Dictyostellium mucoroides and D. minutum. Especially, P pallidum. were found in 30 area and the highest site presence. Eight dictyostelid species was described firstly in this study: D areum var. luteolum, D. delicatum, D. deminutivum, D. implicatum, D. microsporum, D. mucoroides var. stoloniferum, D septentrionalis, and P. candidum.

• Journal of the Korean Solar Energy Society
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• v.23 no.4
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• pp.71-80
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• 2003

The purpose of this study is to analyze the window area ratio distribution of building facade in Tokyo metropolitan area. The survey was carried out in Marunouchi, Kanda, Kasai and Todoriki district. The results of this study were as follows; to propose of window area ratio production method, analyzed and surveyed window area ratio of each district building-used and to compared every wall window area ratio of building. Every wall window area ratio of office district is $20\sim40%$, ones of non-office district is 15% or 35%. Residential area results are every wall window area ratio of apartment is 35%, ones of a house is 15%. To increase of office building to appear that Kanda, Kasai added window area ratio. But, Marunouchi, Todoriki wad not this tendency. Above mentioned results are made out database.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05a
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• pp.59-63
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• 2000

The conventional tracking testing as IEC-60587 is widely used in surface aging measurement of outside insulator because those testing can carry out very short time in Lab testing. Also IEC-60587 testing is able to offer the standard judgement of relative degradation level of outside HV machine. Therefore it is very useful method compare to previous conventional tracking testing method and effective Lab testing method. But surface discharges(SD) have very complex characteristics of discharge pattern so it is required estimation research to development of precise analysis method. In recent, the study of IIR-camera is carrying out discover of temperature of power equipment through condition diagnosis and system development of degradation diagnosis. In this study, SD occurred from IEC-60587 is measured with partial temperature distribution in real time, the degradation grade of SD is analyzed through produced patterns in IEC-60587 according to applied time.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.1
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• pp.9-17
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• 2001

A numerical study has been carried out on the evolution of the particle size distribution for unipolar charged particles that experience coagulation in an alternating electric field. The collision frequency function of charged particles was analytically derived. The log-normal size distribution function is utilized for representing a poly-disperse size distribution and the moments of the particle size distribution are used to solve the general dynamic equation considering only AC electric force effect. The results are compared with the effects of brownian coagulation.

• Journal of Aerospace System Engineering
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• v.13 no.5
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• pp.24-31
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• 2019

In this study, we analyzed the cause of the burn out phenomenon in the power distribution system for aircraft and proposed the improvement method. The power distribution device for aircraft has an AC and DC, and there is a rectifier between the two devices. The capacitors in the power board burn out when the power is turned on and off. The main reason for this is the excessive voltage caused by the inductance built into the rectifier. The cases that can cause a failure are classified. The impact was analyzed and the solution was established through the experimental method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.862-875
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• 1996

The CTD data observed in the sea northwest of Cheju Island have been analyzed to figure out the seasonal circulation around Cheju Island. Warm and saline waters flow into the Yellow Sea through the middle region of the Yellow Sea in winter and along the west coast of Korean Peninsula in summer. On the other hand, cold and less saline waters flow out of the Yellow Sea through the middle region in summer and along the west coast of Korean Peninsula in winter. These flows make the seasonal circulation around Cheju Island. As dynamics, the monsoon wind and the variation of Kuroshio transport have been suggested. Comparing the observational result, the circulation driven by the variation of Kuroshio transport is strengthened by monsoon winds in the numerical model.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.383-388
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• 2008

We are now developing a CFD program, AIRVIEW, with several numerical models and the SIMPLER solving method for constructing flow field and thermal comfort. This study is carried out for evaluating an accuracy of AIRVIEW. Comparisons of accuracy are carried out using Phoenics Version 3.4. In this study, we compare the turbulent kinetic energy distribution and local turbulent Re number obtained with Phoenics with those results simulated by AIRVIEW for three kinds of duct. It is observed from comparison of results that the turbulent kinetic energy values are significant due to the large velocity gradients in the region of flow. Numerical results for turbulent kinetic energy distribution and local turbulent Re number are that a good degree of agreement is found.