• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.93-100
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• 2001

The analysis and control of a new type unsymmetrical slotted self-bearing step motor for small angle control is presented. The motor actuator is used for both motor and bearing functionality without any additional coil windings or electromagnets for bearing functionality. A circular-arc, straight-line permeance model for the fringing effect is presented. An unsymmetrical slotted self-bearing step motor layout and control algorithm are described. A new control current generation method using the electromagnets layout geometry, which needs no additional current for bearing functionality, is proposed. As the result of this analysis the fringing effect largely influences on the system characteristics. especially in torque. Even if the bearing functionality is added into the motor functionality, it is shown that the magnitude of torque is not changed.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.830-833
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• 2005

SDM(Structural Dynamics Modification) is to improve dynamic characteristics of a structure, more specifically of a base structure, by adding or deleting auxiliary(modifying) structures. In this paper, I will focus on the optimal layout of the stiffeners which are attached to the plate to maximize 1st natural frequency. Recently, a new topology method was proposed by yamazaki. He uses growing and branching tree model. I modified the growing and branching tree model. The method is designated modified tree model. To expand the layout of stiffeners, I will consider non-matching problem. The problem is solved by using local lagrange multiplier without the mesh regeneration. Moreover The CMS(Component mode synthesis) method is employed to reduce the computing time of eigen reanalysis using reduced componet models.

• Journal of Fashion Business
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• v.24 no.6
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• pp.63-79
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• 2020

This study analyze consumers' unconscious visual attention to color and images of internet shopping malls by using eye-tracking method. Twenty-nine participants, including 15 females and 14 males, participated. The average ages of the male and female participants were 27.3 years and 27.7 years, respectively. Ten images of five layouts (multi-composition images, single-model images, gender-composed images, videos, and moving banner images) of internet shopping malls were shown on an eye-tracker computer screen. Quantitative analyses of the eye-tracking responses were conducted. SPSS was used to analyze the descriptive characteristics and to conduct an independent-sample t-test, along with an ANOVA. The data analysis showed that the image area generally had the shortest time to first fixation (TFF), the longest duration of fixation (DOF), the highest number of fixations (NOF), and the highest numbers of revisits(NOR).Notably, visual attention towards female models was high among various images. The results can be used to improve credibility and design online shopping layout with a scientific evidence that helps consumers through their purchase decisions.

• Korean Institute of Interior Design Journal
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• v.14 no.6 s.53
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• pp.236-243
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• 2005

The pre-examination closely beforehand relation between the articles on exhibition and visitors, the visitors and exhibition space, the exhibition space and the articles on exhibition, and the acceptance of various requirements are the matters you should consider in the initial stage when planning the establishment of a museum. Especially, the clear guideline for the layout of exhibition to meet the intention of spectators considered based on the seeing behavior in the exhibition hall (i.e. they see the articles on exhibition in order passively under instructions of the museum or select them by themselves positively etc.), and the moving line of appreciation and the exhibition type seems to be not yet prepared sufficiently. This study can be defined as the study of fundamental background for the architectural guideline for the characteristics of visitor's behavior, the selected moving line in the exhibition hall, the layout against the forced moving line and the type of exhibition space. As a part of this study, we carried out the research and the study for how the movement of visitors and the characteristics of seeing behaviors according to the type of the moving line are shown, based on the type of moving line for seeing suggested by David Dean.

• Journal of the Korean housing association
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• v.22 no.1
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• pp.35-42
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• 2011

The objective of this study is to investigate the functional conformity based on the analysis of the spatial connectivity of block housing using space syntax. Three cases were selected which have important meanings in 1920s. The properties of spatial configuration were derived from an urban-context approach and without urban context analysis, and spatial connectivity and functional conformity were analyzed using references. The results of the study revealed that the arrangement of block housing were different from one another notwithstanding their similar layout characteristics. The relationships between urban streets and housing complexes were identified, and the public spaces were being arranged as semi-public spaces, whereas blocks as private spaces by separating functions. This study provides the implications for the planning of low rise-high density housings by means of analyzing the spatial connectivity of the spatial layout characteristics of European block housing, recognizing the relationships between urban communities and housing complexes.

• Korean Institute of Interior Design Journal
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• v.13 no.5
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• pp.114-124
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• 2004

Most previous studies, in general, related to housing needs have analyzed the data from self-administered survey or interview using questionnaire or simple 2D floor plan. This study was Intended to suggest how to increase the reliability and effectiveness of such survey methods in examining the residents' housing needs. In order to accomplish the purpose, the two kinds of surveys using Web based VR media and typical questionnaire were peformed. The same questions were used for these two surveys, and they included the furniture characteristics, use of each room, adjustment of room size, preferences for interior colors, preferred furniture in living room, space layout of floor plan, housing life style, and preference for housing characteristics. The answer differences between these two were analyzed. The subjects were 402 housewives who lived in apartment houses in Haeundae, Busan. Finding were as follows: first, the media method was more likely to be effective than typical questionnaire survey in explaining housing needs for the adjustment of room size in housing unit plan. Second, the media method was more realistic and reliable than the other in comprehending the needs for the interior colors. Last, the VR media tended to be more effective than the other in understanding the space layout of floor plan. This research sheds light on the utilization of visual instrument for the analysis of needs related to space use.

• Journal of the Korea Society for Simulation
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• v.14 no.2
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• pp.93-103
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• 2005

This paper presents characteristics of a virtual human's navigation using a limited perception-based mapping. Previous approaches to virtual human navigation have used an omniscient perception requiring full layout of a virtual environment in advance. However, these approaches have a limitation on being a fundamental solution for a human-likeness of a virtual human, because behaviors of humans are basically based on their limited perception instead of omniscient perception. In this paper, we integrated Hill's mapping algorithm with a virtual human to experiment virtual human's navigation with the limited perception. This approach does not require full layout of the virtual environment, 360-degree's field of view, and vision through walls. In addition to static objects such as buildings, we consider enemy emergence that can affect an virtual human's navigation. The enemy emergence is used as the variable on the experiment of this present research. As the number of enemies varies, the changes in arrival rate and time taken to reach the goal position were observed. The virtual human navigates by two conditions. One is to take the shortest path to the goal position, and the other is to avoid enemies when the virtual human encounters them. The acquired result indicates that the virtual human's navigation corresponds to a human cognitive process, and thus this research can be a framework for human-likeness of virtual humans.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.5
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• pp.48-56
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• 2000

This study aims to find out the norms and principles reflected in the spatial organization of royal tombs in the Chosun Dynasty through the modern interpretation of traditional oriental philosophy theory. We examined the characteristics of royal tomb sites including Jeshil(Shrine), Hongjunmun, tomb mound, ponds, and attached buildings employing an analysis of the spatial formation and landscape. This study covered 36 tombs of kings and queens in the Chosun Dynasty. The entire layout of royal tombs, including annexed buildings, was informal in may cases. This was due to following the natural contour rather than adhering to certain philosophical principles. The royal tomb site is divided into three zones. Jeshil and pond constitute a space for living people, visitors. Secondly, the semi-scared space includes the space from Hongjunmun to the entrance to the Chungjaka. The last space is for the dead, from the back of Chungjakak to tomb mound. This is in line with the layout of palaces of the Chosun Dynasty which is characterized by "three gates and three zones": outer yard-court yard- back yard. The size of the space for holding memorial ceremonies, from Hongjunmun to the Chungjakak entrance, was set at 900m until the early Chosun Dynasty. Since that time the distance varied according to the land topography due to the influence of metaphysics. It can be summarized that the spatial organization of royal tombs in the Chosun Dynasty is based on the Confucianism value, the natural contour of the site, and inner spiritual value.ual value.

• The Transactions of the Korean Institute of Power Electronics
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• v.20 no.6
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• pp.558-565
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• 2015

Gallium nitride high-electron mobility transistor (GaN HEMT) is the strongest candidate for replacing Si MOSFET. Comparing the figure of merit (FOM) of GaN with the state-of-the-art super junction Si MOSFET, the FOM is much better because of the wide band gap characteristics and the heterojunction structure. Although GaN HEMT has many benefits for the power conversion system, the performance of the power conversion system with the GaN HEMT is sensitive because of its low threshold voltage ($V_{th}$) and even lower parasitic capacitance. This study examines the characteristics of a phase-shifted full-bridge dc-dc converter with cascode GaN HEMT. The problem of unoptimized dead time is analyzed on the basis of the output capacitance of GaN HEMT. In addition, the printed circuit board (PCB) layout consideration is analyzed to reduce the negative effects of parasitic inductance. A comparison of the experimental results is provided to validate the dead time and PCB layout analysis for a phase-shifted full-bridge dc-dc converter with cascode GaN HEMT.

• Journal of the Korean Society of Industry Convergence
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• v.23 no.6_1
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• pp.907-915
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• 2020

Specification selection, Layout, specifications and combinations of Power Drives, and Ship motions were studied for FGPP(Floating Gas-fired Power Plants), which are still needed in areas such as the Caribbean, Latin America, and Southeast Asia where electricity is not sufficiently supplied. From this study, the optimal equipment layout in ships was derived. In addition, the difference between engine and turbine was verified through LCOE(Levelized Cost of Energy) comparison according to the type and combination of Power Drives. Analysis of Hs(Significant Height of wave) and Tp(spectrum Peak Period of wave) for places where this FGPP will be tested or applied enables design according to wave characteristics in Brazil and Indonesia. Normalized Sloshing Pressures of FGPP and LNG Carrier are verified using a sloshing analysis program, which is CFD(Computational Fluid Dynamics) software developed by ABS(American Bureau of Shipping). Power Transmission System is studied with Double bus with one Circuit Breaker Topology. A nd the CFD analysis allowed us to calculate linear roll damping coefficients for more accurate full load conditions and ballast conditions. Through RAO(Response Amplitude Operator) analysis, we secured data that could minimize the movement of ships according to the direction of waves and ship placement by identifying the characteristics of large movements in the beam sea conditions. The FGPP has been granted an AIP(Approval in Principle) from a classification society, the ABS.