• Title/Summary/Keyword: Bi-stable

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Electrical Properties with Annealing Temperature of SBN Thin Film (SBN 박막의 열처리온도에 따른 전기적인 특성)

  • Kim, Jin-Sa
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.6
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    • pp.1083-1086
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    • 2010
  • The $Sr_{0.7}Bi_{2.3}Nb_2O_9$ thin films were deposited on Si substrate using RF magnetron sputtering method. And the SBN thin films were annealed at 650~800$[^{\circ}C$]. The surface rougness showed about 0.42[nm] in annealed thin film at $650[^{\circ}C$]. The dielectric constant(150) of SBN thin film was obtained by annealing temperature above $700[^{\circ}C$]. The voltage dependence of dielectric loss showed a value within 0.02 in voltage ranges of -10~+10[V]. The dielectric constant characteristics showed a stable value with the increase of frequency. Also, the SBN thin films annealed at $750[^{\circ}C$] showed a fatigue-free characteristics up to $1.0\times10^8$ cycles.

On the Sealing Characteristics Analysis and Design of Bi-Polymer O-ring Seals

  • Kim, Chung Kyun;Ko, Young Bae;Cho, Seung Hyun
    • KSTLE International Journal
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    • v.2 no.1
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    • pp.40-45
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    • 2001
  • The paper deals with a non-linear finite element analysis of the thermomechanical distortions of an elastomeric O-ring seal including a temperature gradient. Axial compression of O-ring seals, as well as the influence of the temperature gradients and various O-ring seal models, are investigated based on the axisymmetric analysis. The highest temperature occurs near the interface of the O-ring between the dovetail groove bottom and the O-ring seal. The calculated FEM results indicate that the composite O-ring with the diametral ratio, 0.8 shows very stable and recommendable compared with other seal models far elevated temperatures and corrosive environments.

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Development of the Character Constancy Concept: Self and Others (아동의 항상성개념 발달에 관한 연구 - 자신 및 타인의 개인특성을 중심으로 -)

  • Kim, Chang Ha
    • Korean Journal of Child Studies
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    • v.8 no.1
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    • pp.15-29
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    • 1987
  • The purpose of the present research was to investigate (I) the acquisition of character constancy of self and others as a function of age; (2) the pattern of acquisition of character constancy, and (3) the relationships between character constancy and conservation of number and mass. The subjects of this study were 160 children, 20 boys and 20 girls at each grade level, kindergarter through grade 3. The Character Constancy Tasks devised bi Rotenberg (1982) and conservation task of number and mass were administered to each child. Chi square, Guttman Scale analysis and Pearson's Correlation were used for the statistical analysis of data. The findings showed that there was increase with age in character constancy of others and of sell in that there was increase with age in children's belief that the characteristics of another person are stable across time and consistent despite changes in a person's appearance. Character constancy of others and of self were acquired in the developmental stages of identity, stability, and consistency. Character constancy of others and self correlated with the conservation of number and mass.

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Use of mini-implants to avoid maxillary surgery for Class III mandibular prognathic patient: a long-term post-retention case

  • Suh, Hee-Yeon;Lee, Shin-Jae;Park, Heung Sik
    • The korean journal of orthodontics
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    • v.44 no.6
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    • pp.342-349
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    • 2014
  • Because of the potential morbidity and complications associated with surgical procedures, limiting the extent of orthognathic surgery is a desire for many orthodontic patients. An eighteen-year-old woman had a severe Class III malocclusion and required bi-maxillary surgery. By changing the patient's maxillary occlusal plane using orthodontic mini-implants, she was able to avoid the maxillary surgery; requiring only a mandibular setback surgery. To accurately predict the post-surgery outcome, we applied a new soft tissue prediction method. We were able to follow and report the long-term result of her combined orthodontic and orthognathic treatment. The changes to her occlusal plane continue to appear stable over 6 years later.

A Design of Voltage-to-Frequency Converter (입력전압에 비례하는 주파수 신호 생성 회로의 설계)

  • 최진호
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.189-192
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    • 2002
  • In this work, a Voltage-to-Frequency Converter.(VFC) in which the output frequency is proportional to the input voltage is proposed. To obtain temperature stable characteristics the VFC is designed by using two bandgap references. The difference between simulated and calculated values is less than about 5% in output characteristics. In the VFC using BiCMOS the temperature variation of sample output frequencies is less than $\pm$0.5% in the temperature range -$25^{\circ}C$ to 75$^{\circ}C$. And the CMOS VFC has error less than $\pm$0.8% in the temperature range -$25^{\circ}C$ to 75'$^{\circ}C$.

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Broadband Microstrip Patch Antenna

  • Lee Ho-Jun;Lee Jae-Young;Kim Jong-Kyu
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2003.11a
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    • pp.230-233
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    • 2003
  • In this paper, the wideband microstrip patch antennas for the Personal communications Service $(PCS\;:\;1750\~1870\;MHz)$ and International Mobile Telecommunications-2000 $(IMT-2000\;:\;1920\~2170\;MHz)$ dual band are studied. Experimental and simulation results on the dual band antenna are presented. Simulation results are in good agreement with measurements. The experimental and simulation results confirm the wideband characteristics of the antenna. The studied antenna satisfied the wideband characteristics that are required characteristics for above 420 MHz impedance bandwidth for the PCS and IMT-2000 dual band antenna. In this paper, through the designing of a dual band antenna, we have presented the availability for PCS & IMT-2000 base station antenna. An impedance bandwidth of $31\%(VSWR<1.5,\;615\;MHz)$ and a maximum gain of 7dBi can be achieved. The radiation pattern is stable across the passband.

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A Study on Sb2O3 Beam Tuning and Monitoring in Antimony Implantation - (안티몬 이온주입시 Sb2O3 빔튜닝 방법 및 모니터링 연구)

  • 김상용;최민호;김남훈;정헌상;장의구
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.5
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    • pp.476-480
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    • 2004
  • The characteristics of antimony implants are relatively well-known. Antimony has lower diffusion coefficient, shorter implantation range, and smaller scattering as compared with conventional dopants such as phosphorous and arsenic. It has been commonly used in the doping of buried layer in Bi-CMOS process. In this paper, characteristics and appropriate condition of monitoring in antimony implant beam tuning using Sb$_2$O$_3$were investigated to get a reliable process. TW(Thema Wave) and R$_{s}$(Sheet Resistance) test were carried out to set up condition of monitoring for stable operation through the periodic inspection of instruction condition. The monitoring was progressed at the point that the slant of R$_{s}$ varied significantly to Investigate the variation of instruction accurately.

Expression of de novo Designed High Nutritional Peptide (HEAAE) in Tobacco

  • Kim, Jae-Ho;Lee, Chang-Kook;Hong, Bun-Shik
    • Journal of Microbiology and Biotechnology
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    • v.7 no.2
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    • pp.138-143
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    • 1997
  • We have designed and constructed a gene encoding novel high essential amino acid encoding protein(HEAAE). The resultant DNA fragment was tested for in vitro and in vivo expression and then cloned into plant expression vector pBI121, under the control of the cauliflower mosaic virus 35S promoter. Agrobacterium tumefaciens, strain LBA4404, was subsequently transformed with this new construct and Nicotiana tabacum var. Xanthi transgenic plants were obtained. DNA analysis by Southern procedure confirmed the presence of the multi-copy number of genes in the transformed plants. Analysis of RNA and protein synthesized in these transgenic plants demonstrated the stable expression of this gene.

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Thermo-pneumatic Micro Actuator with Bi-stable Membrane (좌굴과 상변화를 이용한 micro actuator 의 개발 및 해석)

  • Song, Gwi-Eun;Kim, Jeong-Sik;Kim, Kwang-Ho;Lee, Yoon-Pyo
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.233-238
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    • 2003
  • A brand-new micro actuator is introduced in this paper. This device is one of thermo-pneumatic actuators, and based on two distinct principles of snap-through buckling and phase change. These coupled phenomena affect each other positively and will outrun the performance of an ordinary thermo-pneumatic actuator. Our efforts are focused on comprehensive analysis on the driving force of the actuator. For the analysis, we explain each principle and offer approximated models for the buckling and phase change. The calculation results from each model are compared to experimental data. The comparison between prediction from models and data from experiments is within the satisfaction in spite of a lot of approximations.

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Ozone Density Estimation and Stable Supply in the Thin Film Growth

  • Lim, Jung-Kwan;Park, Yong-Pil;Oh, Geum-Gon
    • Transactions on Electrical and Electronic Materials
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    • v.2 no.2
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    • pp.42-45
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    • 2001
  • An ozone condensation system is evaluated from the viewpoint of an ozone supplier for Bi-superconductor thin film growth. An ozone condenser by a selective adsorption on the silica gel surface is constructed. Ozone density is evaluated by three methods; ultraviolet absorption, thermal decomposition and Q-mass analyzing methods. Thermal decomposition method is found to be available to the density evaluation from dilute to highly condensed ozone. The highest ozone density condensed by the adsorption method is evaluated to be 97 mol%.

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