• Journal of Advanced Marine Engineering and Technology
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• v.32 no.8
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• pp.1129-1140
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• 2008

Many turbulence models have been developed in order to analyze the flow characteristics in an engine cylinder. Watkins introduced k-${\varepsilon}$ turbulence model for in-cylinder flow, and Reynolds modified turbulence dissipation rate by applying rapid transformation theory, Wu suggested k-${\varepsilon}-{\tau}$ turbulence model in which length scale and time scale are separated to introduce turbulence time scale, and Orszag proposed k-${\varepsilon}$ RNG model. This study applied the models to in-cylinder flow induced by intake valve and piston moving. All models showed similar flow fields during early stage of intake stroke. At the end of compression stroke, ${\kappa}-{\varepsilon}$ Watkins, ${\kappa}-{\varepsilon}$ Reynolds and ${\kappa}-{\varepsilon}$ RNG predicted well second and third vortex, especially ${\kappa}-{\varepsilon}$ RNG produced new forth vortex near central axis at the lower part of cylinder which was not predicted by the other models.

• Structural Engineering and Mechanics
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• v.51 no.1
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• pp.111-130
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• 2014

The aim of this study is to investigate the effects of the beam aspect ratio(L/h), hole diameter, hole location and stacking layer sequence ($[0/45/-45/90]_s$, $[45/0/-45/90]_s$ and $[90/45/-45/0]_s$) on natural frequencies of glass/epoxy perforated beams under room and high (40, 60, 80, and $100^{\circ}C$) temperatures for the common clamped-free boundary conditions (cantilever beam). The first three out of plane bending free vibration of symmetric laminated beams is studied by Timoshenko's first order shear deformation theory. For the numerical analyses, ANSYS 13.0 software package is utilized. The results show that the hole diameter, stacking layer sequence and hole location have important effect especially on the second and third mode natural frequency values for the short beams and the high temperatures affects the natural frequency values significantly. The results are presented in tabular and graphical form.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1155-1162
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• 2004

This research proposes a new risk analysis method in order to guarantee successful performance of construction projects. The proposed risk analysis methods consists of four phases. First step, AHP model can help contractors decide whether or not they bid for a project by analysing risks involved in the project. Second step, the influence diagraming, decision tree and Monte Carlo simulation are used as tools to analyze and evaluate project risks quantitatively. Third step, Monte Carlo simulation is used to assess risk for groups of activities with probabilistic branching and calendars. Finally, Fuzzy theory suggests a risk management method for construction projects, which is using subjective knowledge of an expert and linguistic value, to analyze and quantify risk. The result of study is expected to improve the accuracy of risk analysis because three factors, such as probability, impact and exposure, for estimating membership function are introduced to quantify each risk factor. Consequently, it will help contractors identify risk elements in their projects and quantify the impact of risk on project time and cost.

• Journal of the Korean Institute of Telematics and Electronics
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• v.6 no.3
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• pp.12-23
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• 1969

In this paper, the current distribution on a 6 points fed linear antenna is theoretically introduced. The antenna that we call the 6 points fed linear antenna is an antenna which are fed by emf E1 at the first two points, emf E2 at the second two points, and emf E3 at the third two points. symmetrical with respect to the center. In this analysis, Hallens theory has been extended with the approximation in the same order.

• Journal of the Korean housing association
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• v.17 no.3
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• pp.89-98
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• 2006

The purpose of this study was to survey curriculum of the department of housing and to develop housing welfare educational program in order to offer the information helpful to the professional of housing education and housing policy makers. Documentary research and content analysis methods were used in this study. Data drawn from internet homepage of each universities and public institutions. The major results of this study are as follows. 1) There were 30 universities which has related to the department of housing and the name of major was very various. The half of their curriculum were housing and interior design. 2) The housing welfare educational program should be step by step. The first is basic step to team basic theory of housing and to establish concept of housing welfare. The second is application and practice step of housing design and housing policy and housing economics. The third is specific application step to consider that who were taker from the housing welfare policy and to take practical training in field.

• Journal of The Korean Digital Architecture Interior Association
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• v.9 no.3
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• pp.47-57
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• 2009

The purpose of this study is to propose the design elements useful to give place identity to street space. The theory for place identity is studied and the components-Physical element, Sense, Program, Activity, Context-for identity of place is created. In the case study of SamcheongdongGil, the qualitative research method of Free Picturing Technique and Cognitive Mapping is executed and the samples gathered from the research are analyzed. In the process of analysis, the contents of qualitative evaluation by users is put in order as components for identity of place. Moreover, the design elements for street space are extracted from the case study and theories of urban design. The design elements are summarized as the followings: street pattern with high permeability, various streetscapes, greenscapes, semi public(private) spaces, the third places, public arts, transparent facades, and outdoor activities. Finally, the fruits and boundary of this study are described and the importance of place identity is.

• Journal of the Korean Society of Costume
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• v.60 no.3
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• pp.1-9
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• 2010

The purpose of this study is to develop Blue-Jean Design for Ideal Body Shape. The final aim of Fashion design is looks beauty of people by optical illusion. This study is based on Gestalt therapy and, is blue jeans design using optical illusion of vertical line for ideal beauty body image. Optical illusion for blue-jean design effect to achieve the ideal body shape. We can accumulate the preceding study for modern clothing from design and the related optical illusion effects. Vertical line stitches have all the advantages especially in pants design. I design blue jeans using optical illusion theory. The results of this study are as follows: First, Vertical line helps that jean has the long body shape effectively. Second, Jeans which have two or more vertical lines is more effective than simple Jean in order to make slim body shape. Third, Appropriate position of horizontal lines can be effective to make long body shape. Fourth, Top stitch, pin-tuck and pleats can be applied to vertical or horizontal lines instead of cutting lines.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.4 s.97
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• pp.474-482
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• 2005

A theoretical method is presented to investigate the thermoelastic and dynamic response of functionally graded material (FGM) rectangular plates made up of metal and ceramic. The temperature is assumed to be constant in the plane of the plate and to vary in the thickness direction only. Material properties are assumed to be temperature-dependant, and vary continuously through the thickness according to a power law distribution in terms of the volume fraction of the constituents. The third order shear deformation theory (TSDT) to account for rotary inertia and transverse shear strains is adopted to formulate the theoretical model. The modal analysis technique is used to develop the analytic solutions of the dynamic problem. The effect of material compositions and temperature fields is examined. The present theoretical results are verified by comparing with those from finite element analysis by ANSYS.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.1
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• pp.35-44
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• 2001

A simulated floating inductor using two fully-differential OTA's and a capacitor is presented. The theory of operation is described and experimental results are used to verify theoretical predictions. The results show close agreement between predicted behavior and experimental performance. The proposed floating inductor has about two times higher Q factor than conventional designs. The application of the inductor to a ladder type third order ellitic low pass filer is also presented.

• Journal of Korean Home Economics Education Association
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• v.8 no.2
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• pp.91-104
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• 1996

This study was to develop and to suggest a lesson plan for the area of‘Human Development and Family Relationship’in home economics for junior high school, based on Thelen’s Group Investigation Model’. Group investigation model by Thelen was developed from the theory that the education with special purpose such as societic knowledge is a method to lesson one’s conflict. This study further developed from three main concepts： inquiry, knowledge and activities of learning groups. This model can be used for any age and any subjects in order to solve the arised problems, rather than to accept pre-organized and pre-decided informations. This study is organized around activities for seeking and practicing the rages of action to create dispersal home. First, one unit ‘Understanding of Family’was chosen that concerns and suitable for group investigation model. Second, From the chosen chapter and problem were analyzed organized. Third, the chosen problem were re-analyzed, then a model lesson for group investigation was proposed.