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VISSIM에서 우회전 차량 패턴에 영향을 미치는 parameter 에 관한 연구
정회승,이용재,김태완(Kim, Tae-Wan) 대한교통학회 2008 대한교통학회 학술대회지 Vol.58 No.-
최근 미시적으로 교통 분석을 수행함에 있어 대부분 시뮬레이션 분석 방법을 선호하고 있다. 시뮬레이션 분석을 통한 다수의 연구 내용에서 확인할 수 있듯이 정산과정의 적정성에 따라 그 결과의 신뢰도가 달라지므로 미시적 시뮬레이션 구현 시 정산과정은 매우 중요하다. 그리고 그 정산과정에서 고려해야할 많은 parameter들을 지정하고 수정하는 과정이 역시 중요하다. FHWA guideline에서는 정산과정이 용량과 같은 몇몇 중요 parameta를 이용하여 이루어지지는 않는다고 명시하고 있다. 종종 지역에 따라 몇몇 parameters를 이용하여 정산 모델을 최적화하고 있지만 상황에 따라 모델은 비현실성을 띄게 된다. 그러므로 분석하고자 하는 도로 조건, 교통 조건에 따라 그 정산 모델이 달라져야 할 것이다.
윤현상,정회승,임인호,윤광희,김준한,박창엽 한국전기전자재료학회 1997 電氣電子材料學會誌 Vol.10 No.5
It this paper, the piezoelectric and electro-induced strain properties of (P $b_{1-}$2x/3/B $i_{x}$ )[N $i_{1}$3/N $b_{2}$3/)$_{0.4}$( $Ti_{0.6}$Z $r_{0.4}$)$_{0.6}$] $O_3$ceramics (x=0, 0.005, 0.02) were investigated with the substitution of B $i^{3+}$, and the feasibility of the application for bimorph actuator was evaluated by measuring the dynamic properties of the piezoelectric bimorph fabricated with above ceramics. Dielectric constant was enhanced with the increase of B $i^{3+}$ substitution, and appeared the maximum value of 5032 at x=0.01 composition. Increasing the substitution of B $i^{3+}$, the electromechanical coefficient( $k_{p}$ , $k_{31}$ ) was increased up to the substitution of 0.5 mol% B $i^{3+}$, showed the value of 0.656, 0.439, respectively. The piezoelectric constant( $d_{33}$ $d_{31}$ ) had the highest value of 344, 825 with the substitution of 0.5 mol% B $i^{3+}$. The strain, generated by 60 Hz AC electric field, had the largest value of 1200($\times$10$^{-6}$ $\Delta$1/1) in the composition with the substitution of 0.5 mol% B $i^{3+}$. The dynamic properties of the bimorph actuator, fabricated with the composition substitution of 0.5 mol% B $i^{3+}$, showed the largest value of 325 $\mu$m at $\pm$150 V square pulse. square pulse.are pulse..
음향 방출 센서용 Pb(Zn,Ni,Nb)O<sub>3</sub>-Pb(Zr,Ti)O<sub>3</sub> 세라믹스의 유전 및 압전 특성
한종대,류주현,정회승,서동희,Han, Jong-Dae,Yoo, Ju-Hyun,Jeong, Hoy-Seung,Seo, Dong-Hir 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.8
In this study, in order to develop composition ceramics for Acoustic Emission (abbreviated as AE) sensor application, the PZT system ceramics was fabricated by conventional solid state reaction method. When x=0.48, the density, electromechanical coupling factor($k_p$), piezoelectric coefficient $d_{33}$ and piezoelectric voltage constant $g_{33}$ of the maximum values of $7.857g/cm^3$, 0.51, 190[pC/N], 52[$10^{-3}mV/N$] were obtained, respectively, suitable for AE sensor.
하소온도 변화에 따른 (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 세라믹스의 유전 및 압전 특성
이갑수,류주현,정회승 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.9
(Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 + 0.04 wt% CeO2 lead-free ceramics were synthesized by conventional sintering process and the effect of calcination temperature on microstructure, dielectric and piezoelectric properties were investigated. Improved piezoelectric properties have been observed at 1,125℃ calcination temperature which show the optimal electrical properties, kp∼0.457, d33∼367 pC/N, Qm∼158 and Tc∼85℃. These results show that the piezoelectric properties can be improved by appropriate calcination temperature. 본 연구에서는 (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 + 0.04wt% CeO2 조성에 하소온도의 변화가 시편의 미세구조, 압전 및 유전 특성에 미치는 영향을 조사 한 결과, 하소온도의 변화는 시표의 결정화에 영향을 미쳐 1,125℃의 하소온도에서 그레인의 크기가 급격히 증가하였고, 약 10.2 ㎛의 균일한 그레인 크기를 나타내었으며, 하소온도가 증가함에 따라 시편의 유전 및 압전 특성은 증가하다 감소하는 경향을 나타내었으며, 1,125℃에서 하소한 시편에서 밀도가 5.614 g/cm3, kp가 0.457, d33가 367 pC/N, Qm이 158의 최댓값을 나타내었다.
임인호,박종주,정회승,이영희 한국전기전자재료학회 2001 전기전자재료학회논문지 Vol.14 No.11
In this study, we investigated amounts, distributions and sizes of pores of multilayer piezoelectric transformer, and predicted heat emission property and electrical characteristics according to designs of internal electrode. Forming densities of device having MLC, fingered and full filled internal electrode structure were 4.73 g/㎤, 4.80 g/㎤, 4.82 g/㎤ and forming porosities were 17.3737%, 13.1475%, 12.6121%, respectively. And sintered densities of MLC structured, fingered and full filled devices were 7.76 g/㎤, 7.75 g/㎤, 7.84 g/㎤ and sintered porosities were 4.0967%, 2.7132%, 2.5317%, respectively. Therefore, we concluded that fingered and full fi1led internal electrode devices, expecially, fingered internal electrode devices had cost-effective effect and maximum poling effect due to higher sintered density and lower porosity than MLC structured device. Also we can predict that they have an effect on good heat emission and high output properties of multilayer piezoelectric transformer.
$0.6Pb(Ni_{1/3}Nb_{2/3})O_3-0.31PbTiO_3-0.09PbZrO_3$ 완화형 강유전체의 전계 유기 상전이 현상
윤만순,장현명,정회승,최병철 한국세라믹학회 1997 한국세라믹학회지 Vol.34 No.6
The possibility of the existence of a field-induced micro-macrodomain switching was proposed and examined using 9 mol % PbZrO3-doped 0.6Pb(Ni1/3Nb2/3)O3-PbTiO3 (PNN-PT) systems having rhombohedral symmetry at room temperature. the thermally depoled (freshly prepard) specimens prepared from the rhombohedral side of the system exhibited a relaxor behavior for the whole range of temperature examined (for T<Tmax), where its MPB is 6 mol% for PbZrO3. However, a micro-macro ferroelectric domain switching was induced by the aging after prepoling (30 kV/cm) at certain critical temperature below Tmax. Examination of the electric field-induced strain and polarization indicated the existence of a "fuzzy" transition zone under the ac high-field between critical (pseudo-Curie) temperature and Tmax. The observed "fuzzy" characteristics were then correlated with a possible existence of the dynamic field-induced quasimacrodomains below Tmax.odomains below Tmax.
음향 방출 센서용 Pb(Zn,Ni,Nb)O3-Pb(Zr,Ti)O3 세라믹스의 유전 및 압전 특성
류주현,한종대,정회승,서동희 한국전기전자재료학회 2016 전기전자재료학회논문지 Vol.29 No.8
In this study, in order to develop composition ceramics for Acoustic Emission (abbreviated as AE) sensorapplication, the PZT system ceramics was fabricated by conventional solid state reaction method. When x=0.48, thedensity, electromechanical coupling factor(kp), piezoelectric coefficient d33 and piezoelectric voltage constant g33 ofthe maximum values of 7.857 g/cm3, 0.51, 190[pC/N], 52[10-3mV/N] were obtained, respectively, suitable for AEsensor. 본 연구에서는 우수한 감도 특성을 갖는 AE센서를 제작하고자 PZT계 조성을 개발하기 그에 따른 압전 및 유전 특성을 조사한 결과,. 시편의 압전상수 d33와 g33가 x를 증가하면 증가하다 감소하는 경향을 나타냈으며 x는 0.48에서 각각 190[pC/N], 52[10-3mV/N]의 값에 도달하였다.