• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.127-129
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• 1996

A 3-dimensional analysis is desired for a magnet of magnetically levitated vehicle because the geometrical shape of the magnet is complicated and nonsymmetric. A FEM package of FLUX3D is used to analyze the characteristic of the magnet. Various quantities could be observed like levitation force, flux density distribution along the air gap, edge and fringing effect, leakage flux pattern, etc. The simulation results from FLUX3D are compared with those of 2-D analysis and test results. There are a little difference between results due to the boundary conditions and magnetized B-H curve of the core.

• Journal of Ocean Engineering and Technology
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• v.25 no.2
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• pp.62-66
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• 2011

In this paper, a liquid-filled long membrane container resting on a horizontal foundation is considered. All of the quantities are normalized to obtain similarity solutions. A system of nonlinear ordinary differential equations with undetermined boundary conditions is solved analytically. The integration of the curvature gives the solutions, which are expressed in terms of the elliptic integrals. A method for finding the shape and characteristic values is proposed for a given cross-sectional volume. The validity of these solutions is confirmed, and some results are shown for characteristic values and shapes.

• Journal of Advanced Marine Engineering and Technology
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• v.10 no.4
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• pp.50-56
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• 1986

This report deals with a study on the boundary layer characteristics of TP620 hydrofoil in the steady state by using two dimensional boundary layer theory. On the basis of complex velocity and laminar and turbulent boundary layer theory, the author attempts to know some tendency by evaluating the performance characteristic values of TP620 hydrofoil working in a uniform flow. In deriving characteristic values, he calculates numerically velocity, momentum thickness, skin friction coefficient, shape factor, and displacement thickness on the TP620 hydrofoil working at each attack angle in a uniform flow. Applying this present numerical calculation using Thwaites' and Head's method, the results of boundary layer on the hydrofoil are shown to be influenced by surface velocity and attack angle.

• Fire Science and Engineering
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• v.9 no.1
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• pp.20-29
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• 1995

The sprinkler head is a component of the sprinkler system intended to discharge water for automatic detection and extinguishment of fires. On this study, thermal characteristic values affecting the sensitivity of the fusible alloy type sprinkler head were obtained and analyzed under heated air stream condition which had constant temperature and velocity. The experiment was carried out under the forced convection condition with both the conductive heat loss considered and neglected. The thermal characteristic values of the sprinkler head were obtained in accordance with the material and shape of the heat responsive element and the conditions of the main body.

• Journal of KSNVE
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• v.11 no.3
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• pp.471-476
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• 2001

This paper focuses on the numerical prediction of airflow-induced sound in DVD drives. As a first step, computational fluid dynamics (CFD) is conducted to evaluate flow field characteristics due to the high-speed disk rotation, and to support the acoustic analysis. Acoustic analogy based on Ffowcs Wi1liams-Hawkings (FW-H) equation is adopted to predict aeroacoustic noise patterns. The integral solution for quadrupole volume source is included to identify the turbulence noise generated inside the DVD tray. The strength of sound pressure revel with respect to rotating speed is discussed to meet upfront demand on the high fidelity product development. The present study also focuses on the noise directivity and examines how much the sound noise is sensitive to change in rotating speed. Near-field noise is strongly affected by the flow field characteristic, which is caused by the complex shape of the tray. For a mid-field, the quadrupole noise play as a counterpart of thickness noise or loading noise, so it generates different sound noise Patterns compared with those in the near field.

• Korean Journal of Digital Imaging in Medicine
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• v.12 no.1
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• pp.65-69
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• 2010

High energy electron beams were to concentrically dose inside a tumor and more energy is a shape decreased of dose. Therefore, it is useful to radiation therapy of a tumor. Also high energy electron beams ionized into collision with a atom in structure material of tissue and it has big changes to dose distribution by multiple scattering. The study had to establish characteristic of electron beams from interaction of electron beams and materials. Experiment method was to measure dependence of electron beam central axis for depth dose curve, field flatness and symmetry and field size dependence. The results were able to evaluate data for a datum pint of electron beam. Also radiotherapy has to be considered for not only energy pencil of lines but characteristic, electron guide and isodose curves distribution.

• Korean Institute of Interior Design Journal
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• no.38
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• pp.209-216
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• 2003

The purpose of this study is to develop furniture design for work space of Office based on the research of furniture design and the survey on the design of the office furniture. The office furniture Is designed in order to use the space flexibly and for the user design in the work space. The furniture type of solo worker on characteristic kinds of works should have a simple shape and it should be safe and easy to move because it has a structural function. The furniture in office should be designed in consideration of moveing line while working. The development of furniture in office which suit human body should be made in consideration of human factors and the study on furniture design in office. As above mentioned, to research and study on the furniture design of working furniture in office which reduces fatigue resulted from labor for office, human factors aspect should be considered, furthermore psychological, mental approach to Ideal solution should be made.

• Journal of the Korean Society of Industry Convergence
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• v.16 no.1
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• pp.14-20
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• 2013

In this study, characteristic of new materials for repairing/reinforcement of sea and underwater structures using urethane were studied experimentally. As a results, following their good result was obtained. Materials and construction methods due to a chemical reaction, so no seams, shape or form, regardless of the variety of civil engineering in the field can be applied. Fast workability, hardening existing concrete compared with 80% in shortening. Than the existing large concrete pouring construction cost could be reduced by more than 30%.

• 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.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.2
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• pp.200-206
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• 2006

An electric power efficiency of electrodeless fluorescent lamp depens on a big relative property of gas, gas pressure, lamp formation, ingredients of magnetic substance and shape and action frequency etc. in lamp. We used magnetic substance that opens self-examination material of electrodeless fluorescent lamp antenna. We used Mn-Zn type as the Ferrite. We have examined resistance, impedance and Q-factor's frequency characteristic by ferrite. Coil turns were changed from 13 to 15 turns to recognize brightness change of lamp by winding number. Optical equipment (LS-100) was used to measure brightness. We could know Q-factor's difference according to material is important part of antenna design. When an electrodeless fluorescent lamp was made using T company's PE22, it showed the highest brightness. As number of winding is increased the brightness increased, and starting characteristic became good.