• Journal of Power Electronics
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• v.8 no.1
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• pp.51-59
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• 2008

This paper addresses several issues concerning the analysis, design, modeling, simulation and development of single-phase, single-switch, power factor corrected AC-DC high frequency switching converter topologies with transformer isolation. A detailed analysis and design is presented for single-switch topologies, namely forward buck, flyback, Cuk, Sepic and Zeta buck-boost converters, with high frequency isolation for discontinuous conduction modes (DCM) of operation. With an awareness of modem design trends towards improved performance, these switching converters are designed for low power rating and low output voltage, typically 20.25W with 13.5V in DCM operation. Laboratory prototypes of the proposed single-switch converters in DCM operation are developed and test results are presented to validate the proposed design and developed model of the system.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.2
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• pp.39-52
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• 2003

This paper deals with an automatic design procedure for the maximum torque density and power factor in a synchronous reluctance motor (SynRM). The focus of this paper is the design relative to the number of flux barrier and the ratio Kw of flux barrier width to iron sheet width of a SynRM under the mechanical constraint. The Finite Elements Analysis (FEA) has been used to evaluate the maximum torque density and power factor with each rotor shape. The proposed procedure allows to define the rotor geometric dimensions starling from an existing mootor or a preliminary design. The maximum torque density and power factor of a SynRM has been resulted with the rotor design variation. To prove the propriety of the designed SynRM, the Digital Signal Processor (DSP) installed experimental devices are equipped and the efficiency characteristic test is Performed.

• The Journal of Sustainable Design and Educational Environment Research
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• v.12 no.2
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• pp.31-42
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• 2013

The purpose of this study was to analyze the school location decision factor with land use planning and urban design. And this research proposed the school location decision factor for urban amenity. This research proved the fact that the school land correlated with the park, the other school land etc. And this result will be used in decision-making-process of land use planning, public land development construction oriental, urban design and city policy.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.813-819
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• 2006

The state of the art for the design of swing ann actuators for optical disc drives is to obtain the high efficient dynamic characteristics, especially for the small size for the mobile information devices, It is affected by the need of consumers who wants the portable digital storage devices maintaining highly functional and removable characteristics of the optical disk drive (ODD). As a necessary consequence, the need of the small form factor (SFF) storage device has been considered as an important part in the information storage technology. In this paper. we suggest a new conceptual miniaturized swing arm type actuator that has high efficient dynamic characteristics as well as satisfies the sensitivity and the heat emission requirements for the SFF-ODD. It also uses a tracking electromagnetic (EM) circuit for a focusing motion. Due to the size constraint, the thermal problem of optical head arises; therefore, we design an efficiently heat emitted structure for the actuator.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.50
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• pp.151-160
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• 1999

The relationship between the product design and product image can be defined using human sensibility. If there is a way to grasp the product value or product design that people want most, it could be possible to make and sell user-oriented products. In human sensibility ergonomics, the categories of design factor can be broken into shape and color of the design. Although, the color is the major factor of the design, however, texture were is also an important factor for the shape. In this study, wall-papers that have various shapes of texture were used for the experiment. The purpose of this study was to conduct a sensibility estimation experiment for the product image, and to estimate the parameters of various textures for creating new textures that could be more suitable for human sensibility.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.4
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• pp.53-63
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• 2007

Seismic design codes are developed mainly based on the observation of the behavior of structures in the high seismicity regions where structures may experience significant amount of inelastic deformations and major earthquakes may result in structural damages in a vast area. Therefore, seismic loads are reduced in current design codes for building structures using response modification factors which depend on the ductility capacity and overstrength of a structural system. However, structures in low seismicity regions, subjected to a minor earthquake, will behave almost elastically because of the larger overstrength of structures in low seismicity regions such as Korea. Structures in low seismicity regions may have longer periods since they are designed to smaller seismic loads and main target of design will be minor or moderate earthquakes occurring nearby. Ground accelerations recorded at stations near the epicenter may have somewhat different response spectra from those of distant station records. Therefore, it is necessary to verify if the seismic design methods based on high seismicity would he applicable to low seismicity regions. In this study, the adequacy of design spectra, period estimation and response modification factors are discussed for the seismic design in low seismicity regions. The response modification factors are verified based on the ductility and overstrength of building structures estimated from the farce-displacement relationship. For the same response modification factor, the ductility demand in low seismicity regions may be smaller than that of high seismicity regions because the overstrength of structures may be larger in low seismicity regions. The ductility demands in example structures designed to UBC97 for high, moderate and low seismicity regions were compared. Demands of plastic rotation in connections were much lower in low seismicity regions compared to those of high seismicity regions when the structures are designed with the same response modification factor. Therefore, in low seismicity regions, it would be not required to use connection details with large ductility capacity even for structures designed with a large response modification factor.

• Korean Journal of Construction Engineering and Management
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• v.8 no.5
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• pp.182-190
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• 2007

The minor construction companies in Korea have grown in focusing on the construction operation field. Also, soft field is vulnerable area, and there are not enough delivery systems, therefore, a capacity of the construction industry expansion and productivity is insufficient. Furthermore, the minor construction companies are losing their areas, because the major construction companies having numerous know-how and ample funds are competitive. As the construction industry are more larger and complicated, the design build methods might be increased in the construction industry and the minor construction companies could have more competitive. Hence, this paper analyzes the success factor in minor construction projects by design build methods focusing on instance $company^{\circ}{\phi}s$ case and survey, and critical success factor deduction and importance degree analysis of this factor using AHP analysis. In addition, this paper gives fundamental data how to manage the construction project effectively for minor construction $companies^{\circ}{\phi}s$ expansion in near future.

• Journal of the Earthquake Engineering Society of Korea
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• v.11 no.2 s.54
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• pp.11-17
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• 2007

In current seismic design practice, the response modification factor (R-factor) is used as a factor to reduce the elastic base shear demand to the design force level. As is well-known, the R-factor is a committee-consensus factor and, as such, highly qualitative and empirical. The relationship between the R-factor and the connection rotation capacity available in a particular structural system has remained a missing link. In this paper, a rational procedure to evaluate the R-factor is proposed. To this end, the relationship between the available connection rotation capacity and the R-factor is defined and quantified using nonlinear pushover analysis. An RRS steel frame designed according to IBC 2000 was used to illustrate and verify the proposed procedure. Nonlinear time history analysis results indicated that the R-factor definition proposed in this study is generally conservative from design perspective.

• Korean Institute of Interior Design Journal
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• v.24 no.2
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• pp.11-20
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• 2015

To make provision for the super-aged society, the senior welfare facility which is a kind of typical physical environment of the nursing service would be expected to perform a very important role in local community. This study was conducted to identify the constructs of the servicescapes of senior welfare facility and to draw analysis indicators of it. For this, we performed literature review based on domestic & foreign government guide, service marketing theory and interior architectural results concerning the physical environment of the senior welfare facility. The result of this study showed as follows: servicescapes of the senior welfare facility could be explained as "a whole set of physical environment to support a variety of services provided by the senior welfare facility for the elderly or services of the kind of tangible clues". Analysis indicators of the senior welfare facility's servicescape could be explained as five factors: safety factor, functional factor, aesthetic factor, ambient factor and social factor. In addition we developed 37 pieces of detailed factors referred to five factors. The evaluation and verification of analysis indicators was carried out through 8 experts in-depth interviews. We inspected importance factor using a 5-point Likert scale, therefore safety factor was 4.41, functional factor was 4.27, aesthetic factor was 3.66, ambient factor was 4.20 and social factor was 4.25. More than anything else, in this study, there is a sense that it has established the concept of servicescape adapted to the senior welfare facility and contained a social element between the employees and the physical environment. Theoretical and practical implications of findings are discussed, and future research directions are proposed. we expect to be a little or benefits to the senior welfare facility corresponding to the future of the super-aged society.

• Journal of Fashion Business
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• v.21 no.2
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• pp.91-104
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• 2017

This study analyzed the difference of selection criteria when buying socks and wearing satisfaction related to socks according to demographic characteristics and fashion interest degree for the adults in their from 20s to 40s. Factor analysis, t-test, ANOVA, and Duncan multiple range test were used for data analysis. The result of factor analysis for selection criteria when buying socks showed that the drawn factors were design and coordination, hygiene and wearing comfort and practicality. The difference analysis results about selection criteria when buying socks showed that design and coordination, hygiene and wearing comfort, and practicality were significantly different according to gender, age, and occupation, and that design and coordination and practicality were significantly different according to marital status. The result of difference analysis for selection criteria when buying socks according to fashion interest degree showed that design, coordination, hygiene, wearing comfort and practicality were significantly different. The result of factor analysis for wearing satisfaction of socks showed that the drawn factors were wearing comfort, hygiene, durability, and design. The difference analysis results about wearing satisfaction of socks showed that design was significantly different according to gender and marital status, wearing comfort and design significantly different according to age, wearing comfort, hygiene, and design were significantly different according to occupation. According to fashion interest degree, wearing comfort and design showed the significant difference.