• Title/Summary/Keyword: rectifying characteristic

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Multivariate Sequential Rectifying Inspection with Applicability to the Motor Vehicle Emission Certified Test (자동차 배출가스보증시험에 다변수 축차검사의 적용에 관한 연구)

  • Jo, Jae-Rip
    • Journal of Korean Society for Quality Management
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    • v.19 no.2
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    • pp.63-77
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    • 1991
  • Currently the problem of air pollution caused by the motor vehicle emission is one of the most serious problems to be solved. Thus we needed the inspection method and technical innovation constraining the motor vehicle emission. In order to establish the more reasonable certified test, the multivariate sequential rectifying inspection plan designed in this paper has been applied to the domestic vehicles by analyzing the statistic characteristics of the emission distribution. This inspection method is designed to satisfy the evaluation measure constraining domestic vehicle emission, and it serves the defect rectifying system and performance certification of catalytic converts. As the prior parameter for the domestic vehicles, we used the data for the catalytic converts which passed the certified test excuted by the EPK. For the case of engine test, we used those data which passed the certified test of domestic vehicles. The multivariate sequential rectifying inspection plan of the vector parameter is able to minimize the average sample number and increase the pass probability of operating characteristic curve.

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Expansion of Operating Mode of 3-Phase Quasi-Resonant DC Link Inverter (3-Phase Quasi-Resonant Inverter의 동작모드 확장)

  • Yang, S.B.;Lee, J.W.;Park, M.H.
    • Proceedings of the KIEE Conference
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    • 1990.11a
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    • pp.267-271
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    • 1990
  • This paper describes a 3-Phase Quasi-Resonant DC Link Inverter (3-phase QRI), which has two operating modes, ie. inverting mode and rectifying mode. First the 3-Phase QRI is simplified and the resonant circuit is analyzed in comparison with two resonant DC-to-DC converters. This analysis shows that the maximum voltage of resonant capacitor is limited to twice the input voltage irrespective of operating modes. A new simple control method in rectifying mode is suggested, which does not require any other element in power circuit. The characteristic of 3-Phase Quasi Resonant Inverter has been verified by simulation using the proposed control method.

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Space Charge Effects at Doped Ⅲ-Ⅴ Compound Semiconductor Interfaces (Doping된 Ⅲ-Ⅴ族 化合物 半導體 界面에서 空間電荷效果)

  • Chun, Jang-Ho
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.2
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    • pp.93-97
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    • 1990
  • Interfacil charge approximations and structures at doped semiconductor interfaces were proposed. Rectifying phenomena at the III-V compound semiconductor (p-GaP, p-InP, n-GaAs)/$CsNO_3$ aqueous electrolyte interfaces were qualitatively analyzed in terms of their cyclic current-voltage characteristics. The current-voltage characteristic curves, the ion adsorption and potential barrier processes at the semiconductor interfaces were verified using continuous cyclic voltammetric methods. The pn or np junction structures and the related rectifying types at the doped semi-condudtor-electrolyte inferfaces are determined by the space charges.

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An Economic Design of Rectifying Inspection Plans Based on a Correlated Variable (대용품질특성치를 이용한 계수선별형 샘플링 검사방식의 경제적 설계)

  • Bai, D.S.;Lee, K.T.;Choi, I.S.
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.4
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    • pp.793-802
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    • 1997
  • A sampling plan is presented for situations where sampling inspection is based on the quality characteristic of interest and items in rejected lots are screened based on a correlated variable. A cost model is constructed which involves the costs of misclassification errors, sampling and screening inspections. A method of finding optimal values of sample size, acceptance number and cutoff value on the correlated variable is presented, and numerical studies are given.

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V-I Curves of p-ZnO:Al/n-ZnO:Al Junction Fabricated by RF Magnetron Sputtering

  • Jin, Hu-Jie;Jeong, Yun-Hwan;Park, Choon-Bae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.6
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    • pp.575-579
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    • 2008
  • Al-doped p-type ZnO films were fabricated on n-Si (100) and homo-buffer layers in pure oxygen at $450^{\circ}C$ of by RF magnetron sputtering. Target was ZnO ceramic mixed with 2 wt% $Al_2O_3$. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure and homo-buffer layers are beneficial to Al-doped ZnO films to grow along c-axis. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are ranged from $1.66{\times}10^{16}$ to $4.04{\times}10^{18}\;cm^{-3}$, mobilities from 0.194 to $2.3\;cm^2V^{-1}s^{-1}$ and resistivities from 7.97 to $18.4\;{\Omega}cm$. p-type sample has density of $5.40\;cm^{-3}$ which is smaller than theoretically calculated value of $5.67\;cm^{-3}$. XPS spectra show that Ols has O-O and Zn-O structures and Al2p has only Al-O structure. P-ZnO:Al/n-ZnO:Al junctions were fabricated by magnetron sputtering. V-I curves show that the p-n junctions have rectifying characteristics.

Electrical Properties of V-I Curve of p-ZnO:Al/n-ZnO:Al Junction Fabricate by RF Magnetron Sputtering

  • Jin, Hu-Jie;So, Soon-Jin;Song, Min-Jong;Park, Choon-Bae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.408-409
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    • 2007
  • Al-doped p-type ZnO films were fabricated on n-Si (100) and homo-buffer layers in pure oxygen at $450^{\circ}C$ by RF magnetron sputtering. Target was ZnO ceramic mixed with 2wt% $Al_2O_3$. XRD spectra show that the Al-doped ZnO thin films have ZnO crystal structure and homo-buffer layers are beneficial to Al-doped ZnO films to grow along c-axis. Hall Effect experiments with Van der Pauw configuration show that p-type carrier concentrations are ranged from $1.66{\times}10^{16}\;to\;4.04{\times}10^{18}cm^{-3}$, mobilities from 0.194 to $2.3cm^2V^{-1}s^{-1}$ and resistivities from 7.97 to $18.4{\Omega}cm$. P-type sample has density of $5.40cm^{-3}$ which is smaller than theoretically calculated value of $5.67cm^{-3}$. XPS spectra show that O1s has O-O and Zn-O structures and A12p has only Al-O structure. P-ZnO:Al/n-ZnO:Al junctions were fabricated by magnetron sputtering. V-I curves show that the p-n junctions have rectifying characteristics.

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One-dimensional Schottky nanodiode based on telescoping polyprismanes

  • Sergeyev, Daulet
    • Advances in nano research
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    • v.10 no.4
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    • pp.339-347
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    • 2021
  • In the framework of the density functional theory combined with the method of non-equilibrium Green functions (DFT + NEGF), the electric transport properties of a one-dimensional nanodevice consisting of telescoping polyprismanes with various types of electrical conductivity were studied. Its transmission spectra, density of state, current-voltage characteristic, and differential conductivity are determined. It was shown that C[14,17], C[14,11], C[14,16], C[14,10] show a metallic nature, and polyprismanes C[14,5], C[14,4] possess semiconductor properties and has a band gap of 0.4 eV and 0.6 eV, respectively. It was found that, when metal C[14,11], C[14,10] and semiconductor C[14,5], C[14,4] polyprismanes are coaxially connected, a Schottky barrier is formed and a weak diode effect is observed, i.e., manifested valve (rectifying) property of telescoping polyprismanes. The enhancement of this effect occurs in the nanodevices C[14,17] - C[14,11] - C[14,5] and C[14,16] - C[14,10] - C[14,4], which have the properties of nanodiode and back nanodiode, respectively. The simulation results can be useful in creating promising active one-dimensional elements of nanoelectronics.

One-dimensional Schottky nanodiode based on telescoping polyprismanes

  • Sergeyev, Daulet
    • Advances in nano research
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    • v.10 no.5
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    • pp.471-479
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    • 2021
  • In the framework of the density functional theory combined with the method of non-equilibrium Green functions (DFT + NEGF), the electric transport properties of a one-dimensional nanodevice consisting of telescoping polyprismanes with various types of electrical conductivity were studied. Its transmission spectra, density of state, current-voltage characteristic, and differential conductivity are determined. It was shown that C[14,17], C[14,11], C[14,16], C[14,10] show a metallic nature, and polyprismanes C[14,5], C[14,4] possess semiconductor properties and has a band gap of 0.4 eV and 0.6 eV, respectively. It was found that, when metal C[14,11], C[14,10] and semiconductor C[14,5], C[14,4] polyprismanes are coaxially connected, a Schottky barrier is formed and a weak diode effect is observed, i.e., manifested valve (rectifying) property of telescoping polyprismanes. The enhancement of this effect occurs in the nanodevices C[14,17] - C[14,11] - C[14,5] and C[14,16] - C[14,10] - C[14,4], which have the properties of nanodiode and back nanodiode, respectively. The simulation results can be useful in creating promising active one-dimensional elements of nanoelectronics.

Unusual Electrical Transport Characteristic of the SrSnO3/Nb-Doped SrTiO3 Heterostructure

  • De-Peng Wang;Rui-Feng Niu;Li-Qi Cui;Wei-Tian Wang
    • Korean Journal of Materials Research
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    • v.33 no.6
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    • pp.229-235
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    • 2023
  • An all-perovskite oxide heterostructure composed of SrSnO3/Nb-doped SrTiO3 was fabricated using the pulsed laser deposition method. In-plane and out-of-plane structural characterization of the fabricated films were analyzed by x-ray diffraction with θ-2θ scans and φ scans. X-ray photoelectron spectroscopy measurement was performed to check the film's composition. The electrical transport characteristic of the heterostructure was determined by applying a pulsed dc bias across the interface. Unusual transport properties of the interface between the SrSnO3 and Nb-doped SrTiO3 were investigated at temperatures from 100 to 300 K. A diodelike rectifying behavior was observed in the temperature-dependent current-voltage (IV) measurements. The forward current showed the typical IV characteristics of p-n junctions or Schottky diodes, and were perfectly fitted using the thermionic emission model. Two regions with different transport mechanism were detected, and the boundary curve was expressed by ln I = -1.28V - 13. Under reverse bias, however, the temperature- dependent IV curves revealed an unusual increase in the reverse-bias current with decreasing temperature, indicating tunneling effects at the interface. The Poole-Frenkel emission was used to explain this electrical transport mechanism under the reverse voltages.

Electrical Characteristics of the SiC SBD Prepared by using the Facing Targets Sputtering Method (대향 타겟 스퍼터링법으로 제작한 SiC SBD의 전기적 특성)

  • Lee, Jinseon;Kang, Tai Young;Kim, Kyung Hwan
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.1
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    • pp.27-30
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    • 2015
  • SiC based Schottky barrier diodes were prepared by using the facing targets sputtering method. In this research, 4H-SiC polytypes of SiC were adopted and Molybdenum, Titanium was employed as the Schottky metal of the metal-semiconductor contacts. Both structures showed the rectifying nature in their forward and reverse J-V characteristic curve and the ideality factors calculated from these plots that were close to unity were represented the nearly ideal behavior. Difference of Schottky barrier height between prepared devices was also corresponding with the electrical characteristics of themselves. Therefore the suitability of the facing targets sputtering method for fabrication of Schottky diodes could be suggested from these results.