• Journal of Electrical Engineering and Technology
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• v.12 no.6
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• pp.2307-2316
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• 2017

The aim of this paper is to provide an optimal design of in-wheel motor for an electric scooter (E-scooter) considering economical production. The preliminary development in-wheel motor, which has a direct-driven outer rotor type attached to the E-scooter's rear wheel without any gear, is introduced first. The objective of the optimal design of this in-wheel motor is to improve the output characteristics of the motor and to have a stator form to facilitate automatic winding. Response surface methodology was used for the optimal design and 2-dimensional finite element method was used for electro-magnetic field analysis. Experimental results showed that the designed and fabricated in-wheel motor could satisfy the required specifications in terms of speed, power, efficiency, and cogging torque.

• Journal of the Korean Society for Precision Engineering
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• v.6 no.4
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• pp.126-135
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• 1989

In this study, in order to perform dynamic design of machine tools reasonably and effectively, a method was formulated to be applicable to the structures connected by joints having elasticity and damping by using substructure synthesis method. And to analyze chatter-free performance, a 3 dimensional cutting dynamics theory was used. Computer program package for the dynamic design of machine tools was developed by combining those and spplied to improvement of performance of NC lathe. Also, the optimization in the structural modifications of machine tool substructure was studied by evaluating the effects of the substructural modifications on total system performance.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.995-996
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• 2007

This study is for a design of a spindle motor for 1.8 inch hard disk drives(HDDs). Equivalent magnetic circuit model is applied for a basic design of the motor, a specific configuration design and magnetic distribution characteristics are confirmed using finite element analysis. Besides, thrust forces generated between rotor and stator core and thrust pad are calculated for pressure analysis of fluid dynamic bearings.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1395-1400
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• 2004

A centrifugal compressor for geothermal heat pump system using R134a as working fluid has been developed. The centrifugal compressor consists of an impeller with splitters, two vaneless diffuser, a low solidity vaned diffuser and a volute. In this compressor, diffuser blade angles are controlled to satisfy both heating and cooling conditions. A aerodynamic design was done by applying the repeating design procedure including a meanline design, a 3D geometry generation and fluid dynamic calculation. In this paper, design and performance prediction results of the compressor are presented.

• The KSFM Journal of Fluid Machinery
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• v.5 no.1 s.14
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• pp.33-41
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• 2002

Low NPSH and high pressure pumps we widely used for turbopump systems, which have an inducer and operate at high rotating speeds. In this paper, a meanline method has been established for the preliminary design and performance prediction of pumps having an inducer for cavitating or non-cavitating conditions at design or off-design points. The method was applied for the performance prediction of a fuel pump. Predicted performances by the method are shown to be in good agreement with experimental results for cavitating and non-cavitating conditions. The established meanline method can be used for the performance prediction and preliminary design of high speed pumps which have a inducer, impeller and volute.

• Information and Communications Magazine
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• v.25 no.12
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• pp.10-18
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• 2008

In this paper, we present a low-power design of H.264 codec based on dedicated hardware and software solution on EMP(ETRI Multi-core platform). The dedicated hardware scheme has reducing computation using motion estimation skip and reducing memory access for motion estimation. The design reduces data transfer load to 66% compared to conventional method. The gate count of H.264 encoder and the performance is about 455k and 43Mhz@30fps with D1(720x480) for H.264 encoder. The software solution is with ASIP(Application Specific Instruction Processor) that it is SIMD(Single Instruction Multiple Data), Dual Issue VLIW(Very Long Instruction Word) core, specified register file for SIMD, internal memory and data memory access for memory controller, 6 step pipeline, and 32 bits bus width. Performance and gate count is 400MHz@30fps with CIF(Common Intermediated format) and about 100k per core for H.264 decoder.

• Journal of the Korean housing association
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• v.16 no.4
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• pp.121-129
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• 2005

The major goal of this study is drawing design plan factors considering residents' life cycle and life style when remodeling design is needed. By drawing such design factors, the study will propose an alternative remodeling design plan. Such design method was defined as Multi-Dimensional module design method. And constructing data-system based on Multi-Dimensional module was secondary goal in this study. The details are as follows: Based on analysis of Residents' demand for remodeling and features of emotion-design applied to remodeling, the system which is suitable for application in remodeling design method was conducted. Based on the type of construction materials, the level value was set up according to emotion-factor application. Also, by conducting coding operation according to the distinction of construction materials, this study seeks the unit drawing method of information for constructing emotion-information system.

• The KSFM Journal of Fluid Machinery
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• v.19 no.5
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• pp.35-41
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• 2016

This paper deals with the design, manufacturing and test evaluation of a hydrostatic bearing applied to a hydraulic model turbine. The design parameters of a hydrostatic bearing, considering machining and assembly tolerances, and recommended values of design parameters are presented. Also the simple design procedure of a hydrostatic bearing by utilizing the reference results is proposed. In order to illustrate the utility and validity of the proposed design procedure, two hydrostatic bearings are manufactured and test evaluation of these bearings are performed. In results, the proposed design procedure can be utilized as an effective tool at the initial design screen of a hydrostatic bearing. However, the 2D bearing governing equation should be solved to obtain the optimal design of a hydrostatic bearing.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.147-156
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• 2007

This study offers a design procedure of optimum cable damper for multi-mode vibration control with nonlinear damper and also investigate the relation between mode and amplitude dependency. The proposed multi-mode damping index, which is defined as a energy loss ratio of cable potential, is a main component of optimization problem of optimum nonlinear damper. In order to include the amplitude dependency of nonlinear damper, it is assumed to exist three kinds of multi-mode patterns such as ambient vibration, support excitation and rain-win induced vibration. The optimum damper exponent depends on amplitude patterns. In case of ambient vibration, optimum factor is less than 0.5. In case of support excitation or rain-wind induced vibration is between 0.5 and 1.0. In this study, the effects of cable sag and inclination angle are included in the asymptotic design equation of damped cable structures.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.05a
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• pp.75-76
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• 2007

Recently with increasing interest in the natural science history education, a lot of natural science museums have been developed in various locations. This project is located in one of the biggest Paleozoic site, Taebak Kangwon-do. This kind museum has had important rolls in terms of education for student, destination for traveling and reservation of important holdover of the old ages. To do those kind of parts, this project has been designed with concepts and themes like; i. being organized with story telling structure with theme "secret of life and earth from Taebak" ii. combining experiences between outdoor experimental search for the real fossils and indoor educational interactions with real size model and moving films. iii. designing with strong identities of Paleozoic era. For the design identities the outer appearance was designed with motive of trilbites in an abstract way and inside was finished with exposed concrete and various size of moving films projected to walls and floor to emphasize real scale experience of the old ages.