• Title/Summary/Keyword: Korean figure

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Characteristics of Flow Pattern and Mass Transfer in a Shaking Vessel with Figure-Eight Circulating Motion (8자 진동교반에 의한 교반조내 유동상태 및 물질전달 특성)

  • Lee, Young Sei;Kato, Yoshihito
    • Korean Chemical Engineering Research
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    • v.53 no.2
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    • pp.174-180
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    • 2015
  • The flow pattern and the solid-liquid mass transfer coefficient in figure-eight shaking vessels were observed by experimental method. The flow patterns, mixing time, power consumption and mass transfer coefficient in the figureeight shaking vessels changed irregularly with increase in the shaking frequency. Any frequency, even in the Fr = 0.095 or more became clear experimentally. The region of the optimum operating condition of the figure-eight shaking was larger than that of the reciprocal shaking. The solid-liquid mass transfer coefficient was correlated with the same correlation as that of the rotary shaking vessel of existing. The gas-liquid mass transfer coefficient of the figure-eight shaking vessel was also correlated with the same type of correlation as that of the rotary shaking vessel of existing.

Analysis of Pull-in-Voltage and Figure-of-Merit of Capacitive MEMS Switch

  • Saha, Rajesh;Maity, Santanu;Devi, Ngasepam Monica;Bhunia, Chandan Tilak
    • Transactions on Electrical and Electronic Materials
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    • v.17 no.3
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    • pp.129-133
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    • 2016
  • Theoretical and graphical analysis of pull-in-voltage and figure of merit for a fixed-fixed capacitive Micro Electromechanical Systems (MEMS) switch is presented in this paper. MEMS switch consists of a thin electrode called bridge suspended over a central line and both ends of the bridge are fixed at the ground planes of a coplanar waveguide (CPW) structure. A thin layer of dielectric material is deposited between the bridge and centre conductor to avoid stiction and provide low impedance path between the electrodes. When an actuation voltage is applied between the electrodes, the metal bridge acquires pull in effect as it crosses one third of distance between them. In this study, we describe behavior of pull-in voltage and figure of merit (or capacitance ratio) of capacitive MEMS switch for five different dielectric materials. The effects of dielectric thicknesses are also considered to calculate the values of pull-in-voltage and capacitance ratio. This work shows that a reduced pull-in-voltage with increase in capacitance ratio can be achieved by using dielectric material of high dielectric constant above the central line of CPW.

Analysis of Upper Torsos Replicas of Elderly Women for Bodice Pattern

  • Shin, Hae-Kyung
    • International Journal of Costume and Fashion
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    • v.3
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    • pp.13-24
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    • 2003
  • The purpose of this study was to examine the changes brought by the upper body form using a three-dimensional human body measurement the gypsum method. The developed plane figure was constructed using paper replica to analyze the dimensional shape of the upper torso and to be able to design clothes suitable for elderly women's physical characteristics. The characteristics are analyzed and compared with existing patterns in order to extract the components for the pattern design. The examination was carried out based on the developed plane figures of upper body surface replicas. Type 1, the bent-forward body form, has a wide gap on the shoulder. In Type 2, the gap of waist line was wide at angulus scapulae point. Type 3 was the thin body form, and the girth of the chest, front interscye breadth and back interscye breadth were more level with one another, compared to the other types. In Type 4, the bent-backward body form, there was a wide gap on front shoulder. Comparison with the developed plane figure and existed pattern, items revealed differences in significance included the front and back interscye width between the measured values of the existed patterns and the developed plane figure. Therefore, the basic components of basic bodice pattern for old women were determined in the up-bust circumference and length of the back.

Compensation Characteristics of 40 Gbps Optical Pulses Depending on Figure of Merit of Dispersion Compensating Fiber (분산 보상 광섬유의 성능 지수에 따른 40 Gbps 광 펄스의 보상 특성)

  • Lee, Seong-Real
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.729-731
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    • 2013
  • The compensation characteristics of 40 Gbps optical signals depending on figure of merit (FOM) of dispersion compensating fiber with dispersion coefficient of -125 ps/nm/km are investigated in this research. Simulation results show that the more fiber span number and launch power increase, the more the effects of FOM of DCF on the compensated signals increase. However, it is also confirmed that the more the effects of optical nonlinearity increase, the more FOM decrease.

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Thickness Optimization of TbFeCo Disks by Computer Simulation (컴퓨터 시뮬레이션에 의한 TbFeCo 광자기 디스크 두께 최적화)

  • 김진홍;권혁전;신성철
    • Journal of the Korean Magnetics Society
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    • v.4 no.3
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    • pp.249-255
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    • 1994
  • Magneto-optical disks with dielectric layers for optical tunning are useful for maximizing the SNR. We have developed a computer program based on characteristic matrix to investigate the best combination of the film thicknesses. We have optimized the thicknesses of the multilayers which were composed of TbFeCo, dielectric, and AI layers at the wavelengh of 830nm. The criterion for the optimization of the film thickness was to maximize the figure of merit with maintaining the low ellipticity and rmre than 10% reflectivity.

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A Study on the Polishing Characteristics for Corrective Polishing of Optical Glass (유리소재의 형상수정 가공을 위한 연마특성)

  • 권기찬;오창진;김옥현;김성청
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.311-315
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    • 2001
  • This paper presents the result of basic study about corrective polishing for arbitrary surface figure. In this study, we researched polishing characteristics on the working condition of optical glass. The abrasive size, relative velocity and working pressure were selected major factors that affect polishing process. The Preston's equation which is the representative model of polishing process was used to model the unit removal shape. The Preston's coefficient and unit removal function were calculated from the polished surface. Applying these results, we have shown that the systematic corrective polishing of arbitary figure is feasible through experiments and analysis.

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Thermoelctric Propretries of Bi2Te3 Fabricated by Mechanical Grinding-Mixing Process (기계적분쇄-혼합공정에 의해 제조된 Bi2Te3 소결체의 열전특성)

  • 이근길
    • Journal of Powder Materials
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    • v.7 no.1
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    • pp.6-11
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    • 2000
  • Two kinds of Bi2Te3 powders, pure Bi2Te3/2vol.%ZrO2, have been prepared by a mechanical grinding process process. Effect of mixing of the powders on thermoelectric of the sintered body has been investigated by measuring Seebeck Coeffcient, specific electric resistivity and thermal conductivity. With an increase in the weight fraction of the Bi2Te3/2vol.%ZrO2 powder from 0 to 40wt.%. Especially, the figure of merit of the mixedBi2Te3 sintered body increases and thereafter dedreases above 40wt.%. Especially. the figure of merit of the mixed Bi2Te3 sintered bodies with mixing of Bi2Te3/2vol.%ZrO2 powder increased about 1.3time in comparison with the value of the specimen before mixing. Mixing of two kinds of Bi2Te3 powders which have different theramal and electric propertries with each other seemed to be useful methob to increase the figure of merit of Bi2Te3 sintered body.

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A Body Measurement and a Classification of Somatotype for Dress Figure (I) (인대 제작을 위한 인체계측 및 체형 분류(I) -국민학교 1,2학년 아동을 대상으로)

  • 김혜경
    • Journal of the Korean Home Economics Association
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    • v.30 no.3
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    • pp.56-62
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    • 1992
  • The purpose of this study was to characterize the somatotype of children and to provide fundamental data for the construction of the dress figure. The subjects for anthropometric measurements were 384 elementary school children aged from 6 to 7 living in Seoul and Pucheon. The data were analyzed statistically according to SPSS/PC + version 3.1. Through the factor analysis, six factors were obtained. The six factors represented the body girth and weight, the height and sleeve length, the trunk length, the shoulder size, the body curvature, and the posture of upper torso, respectively. The subjects were classified into six clusters. Among the six clusters, four clusters covered about 95.9% of the whole subjects were determined as the sources of fundamental data for the children's dress figure.

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The Design and Fabrication of CMOS LNA through De-embedded Verification of the Spiral Inductor (나선형 인덕터의 디임베드 검증을 통한 CMOS LNA 설계 및 제작)

  • Lee, Han-Young;Yoo, Young-Kil
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.12
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    • pp.2269-2275
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    • 2008
  • This paper examined the simulation results after applying not only spiral inductor's 3D EM simulation but also de-embedding technique to reduce the pad's RF effects. When calculating standard deviation with measurement results not only the gain at 0.5GHz${\sim}$4GHz but also noise figure at 1.8GHz${\sim}$4GHz, the simulation results includes de-embedded inductor' model improved gain deviation by 0.171 and noise figure deviation by 0.151 than the results from simulation with foundry inductor equivalent circuit models.

Design of Array Antenna with Active Antenna Element (LNA가 장착된 안테나 소자를 이용한 배열 안테나 설계)

  • 이용기;김성남;이상원;김영식;천창율
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.53 no.5
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    • pp.279-285
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    • 2004
  • In this paper, low noise amplifier(LNA), aperture coupled patch antenna and $4{\times}4$ array antenna are designed in the frequency range from 11.7㎓ to 12㎓. Array antennas with and without LNA at the antenna element are fabricated and the performances are measured including noise figure(NF). The noise figure calculation for overall system was conducted and compared with the measured data to verify our measurement method. The measured overall noise figure of the array antenna with LNA at the antenna element is lower than that of array without LNA as expected.