• Title/Summary/Keyword: Air-guide

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A Study on the Royal Procession Ceremonies in the Yi Dynasty - Focusing on the Analysis of the Systems - (조선왕조 로부(어가행렬) 의례에 관한 연구 - 형식구조의 파악을 중심으로 -)

  • Baik Young-Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.13 no.2 s.30
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    • pp.166-179
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    • 1989
  • This study was undertaken to discuss the frameworks of the gorgeous and magnificent royal procession ceremonies in the Yi Dynasty, thereby exploring the classification systems of 'three stages and five segments' on the basis of cultural anthropology and Korean traditional shamanism of ancestral sacrifices. The ceremonies were classified into three phases of (1) cleanup stage, (2) primary objective attendance stage, and (3) completing stage. Among these phases, p. :mary objective attendance stage was further distributed into five segments of (1) road guide, (2) dressing, (3) royal procession, (4) attendants' procession, and (5) back row procession. The isolates and functions of the royal procession ceremonies in the Yi Dynasty were studied through the application of Levi Strauss's structural methodology.

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Microwave Rectangular Waveguide Measurement of the Engine Oil Dielectric Constant (초고주파 구형도파로를 이용한 엔진 오일의 유전율 측정)

  • Kim, Ki-Hoon;Kim, Young-Ju
    • Tribology and Lubricants
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    • v.27 no.3
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    • pp.156-161
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    • 2011
  • The rectangular waveguide technique can be used to measure the complex permittivity of dielectric material of various thickness and cross section. This paper presents the analysis system of engine oil permittivity at which deterioration of engine oil is measured at the X-band(8-12.5 GHz). The middle of the rectangular waveguide has engine oil case and is connected with VNA(Vector Network Analyzer) for the measurement of the transmission$(S_{21})$ and reflection$(S_11)$ and then the permittivity is extracted. The deterioration of engine oil is proved by the comparison with both the extracted data and reference data. As the additional research, This paper suggest that an accurate permittivity is considered by not only the wave guide length but the air gap between oil case and the waveguide.

A Study of Micro Machining Using Ultra Precision Machine (초정밀 가공기 제작을 통한 미세가공에 관한 연구)

  • 김석원;김상기;정우섭;이채문;이득우
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.97-100
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    • 2004
  • In recent years, a demand for micro-structure machining is increasing by the development of information and optics industries. Micro machining technology is in general well known in the field of lithograghy. However, the requirement of producing micro machine and/or micro mechanism with metal materials will be increased since a variety of workpiece configurations can be easily made. In this paper, ultra precision machine is developed to obtain micro groove and mirror surface using single crystal diamond tool. According to the cutting experiment, no burr was found at the edge of V-grooves, and the surface roughness of copper is about 1~3nm Ra. It is verified that ultra precision machine is effective to high precision machining.

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Investigation on Characteristics of Interior Permanent Magnet Synchronous Motor according to Pole-Slot Combination (매입형 영구자석 동기전동기의 극 수 슬롯 수 조합에 따른 특성에 관한 연구)

  • Bahn, Ji-Hyung;Kwon, Soon-O;Ha, Seung-Hyonng;Hong, Jung-Pyo
    • Proceedings of the KIEE Conference
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    • 2006.07b
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    • pp.771-772
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    • 2006
  • Recently, Interior Permanent Magnet Synchronous Motor(IPMSM) is widely used in the industry applications such as power train for hybrid vehicles and compressor motors of air-conditioner due to its high power density and wide speed range. In designing motors, pole slot combination should be chosen properly according to the use of the motor and driving method in the initial design stage, accordingly there have been many researches about pole slot combination. As a part of the studies, this paper presents a comparison of characteristics of concentrated winding IPMSM, such as back-emf, Total Harmonic Distortion(THD) and core losses for each pole slot combination. By comparing the characteristics of each model, this paper can be a guide or reference in determining pole slot combination in the initial design stage.

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Air-Conditioner Power Source device to meet the Harmonic guide lines (에어컨 전원장치의 고조파 저감)

  • Mun Sang-Pil;Suh Ki-Young;Lee Hyun-Woo;Kim Young-Mun
    • Proceedings of the KIPE Conference
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    • 2001.12a
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    • pp.171-174
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    • 2001
  • This paper proposes a nonlinear impedance circuit composed by diodes and inductors or capacitors. This circuit needs no control circuits and switches, and the impedance .value is changed by the polarity of current or voltage. and this paper presents one of these applications to improve the input current of capacitor input diode rectifiers. The rectifier using the nonlinear impedance circuit id constructed with four diodes and four capacitors in addition to the conventional rectifiers, that is, it has eight diodes and five capacitors, including a DC link capacitor. It makes harmonic components of the input current reduce and the power factor improve. A circuit design method is shown by experimentation and confirmed simulation. It explained that compared conventional pulse width modulated (PWM) inverter with half pulse-width modulated (HPWM) inverter. Proposed HPWM inverter eliminated dead-time by lowering switching loss and holding over-shooting.

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Design and Analysis of a Linear Motor for Slim-line ODD (소형 광디스크 드라이브용 선형 구동기의 설계 및 특성 해석)

  • Shim, Min-Taek;Park, Joon-Hyuk;Baek, Yoon Su
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.794-798
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    • 2002
  • This paper deals with a moving coil type linear motor for fast access of the miniature ODD. This slim-line motor is composed of the mover supported by guide mechanism, the coil wound into it, and the yoke attached to the permanent magnet for stator. The driving force is generated by the PM of the stator and the current in the coils of the mover. Magnetic circuit analysis and Finite Element Method are applied to estimate the thrust force at air gap. In order to compare the force characteristics between two methods, various experiment results are applied to verify on a prototype. Also the flexible modes of the motor are predicted through the FEM and the structural components are modified to locate this on high frequency region.

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The Depth and Angle during Caudal Epidural Approach in Adult (성인에서 미추부 경막외강의 깊이와 각도)

  • Jo, Dae-Hyun;Kim, Myoung-Hee;Choy, Yoon-Keun
    • The Korean Journal of Pain
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    • v.14 no.2
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    • pp.207-210
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    • 2001
  • Backgroud: Caudal blocks have been used for pain management in outpatient clinics. It is important to estimate the proper depth and angle in order to increase the success rate of the procedure. Methods: Data was collected from 60 patients who visited our pain clinic. We measured the depth of the needle's penetration and the angle of the needle at the insertion point when a caudal approach was confirmed by air flow method. We recorded age, sex, body weight and height, and calculated the ponderal index. Results: The depth from the skin to the caudal epidural space was a mean 2-4 cm ($3{\pm}0.4\;cm$). The angle at the needle insertion point was a mean 15-50 degree ($34.9{\pm}6.8$ degree). Conclusions: If we use the mean depth and angle as a guide, complications during the caudal epidural procedure can be avoided.

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A Study on the Optimal Configuration and Performance Improvement of a Micro Cross-Flow Hydraulic Turbine (마이크로 관류수차의 최적형상 및 성능향상에 관한 연구)

  • Zhao, Linhu;Lee, Young-Ho;Choi, Young-Do
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.2
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    • pp.296-303
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    • 2006
  • Recently, micro hydropower attracts attention because of its clean. renewable and abundant energy resources to develop. However, suitable turbine type is not normalized yet in the range of micro hydropower and it is necessary to study for the effective turbine type. Moreover, relatively high manufacturing cost by the complex structure of the turbine is the highest barrier for developing the micro hydropower turbine. Therefore a cross-flow turbine is proposed for micro-hydropower in this study because of its simple structure and high possibility of applying to low head. The purpose of this study Is to further optimize the turbine structure and improve the performance. A guide vane is removed and the runner chamber is made compact using a new air supply method. The results show that the efficiency of the turbine is improved in a wide operating range and the size of the turbine is remarkably reduced.

Design and Analysis of linear motor for slim-line ODD (소형 ODD용 선형 구동기의 설계 및 특성 해석)

  • Shim, Min-Taek;Park, Joon-Hyuk;Baek, Yoon-Su
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.378.2-378
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    • 2002
  • This paper deals with a moving coil type linear motor for fast access of the miniature ODD. This slim-line motor is composed of the mover supported by guide mechanism, the coil wound into it, and the yoke attached to the permanent magnet for stator. The driving force is generated by the PM of the stator and the current in the coil of the mover. Magnetic circuit analysis and Finite Element Method are applied to estimate force at air gap. (omitted)

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Interior noise prediction of the high speed train using ray method (광음향기법을 이용한 한국형 고속전철의 실내소음 예측)

  • 김관주;박진규
    • Proceedings of the KSR Conference
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    • 2000.11a
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    • pp.157-164
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    • 2000
  • This study is about predicting the interior pressure level of the korean high speed train using ray acoustic method. The motor car and the motor and passenger cabin are investigated under the environment of passing open countryside and inside tunnel of 350 km/hr. Calculated sound levels are compared with the proposed sound levels and suggestions about the transmission Joss values of isolating panels inside motor car and the guide lines of allowed sound power limit of motor equipments are provided. Results of TPI car show calculated interior sound level is below the proposed values for both cases of open countryside running and inside tunnel. Since ray acoustic method calculated only air borne noise component, real sound level of the motor car may be higher than prediction. Passenger cabins of TMI, TM5 show higher sound level than the proposed values, so window method was carried out to find the contribution of each panel components and point out the remedy of transmission path. Reduction of sound power of motor equipments should be condisered at the same time.

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