• Title/Summary/Keyword: Cross current

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Preparation and Properties of PVP (poly-4-vinylphenol) Gate Insulation Film For Organic Thin Film Transistor (유기박막 트랜지스터용 PVP (poly-4-vinylphenol) 게이트 절연막의 제작과 특성)

  • Baek, In-Jae;Yoo, Jae-Hyouk;Lim, Hun-Seung;Chang, Ho-Jung;Park, Hyung-Ho
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.4 s.37
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    • pp.359-363
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    • 2005
  • The organic insulation devices with MIM (metal-insulator-metal) structures as PVP gate insulation films were prepared for the application of organic thin film transistors (OTFT). The co-polymer organic insulation films were synthesized by using PVP(poly-4-vinylphenol) as solute and PGMEA (propylene glycol monomethyl ether acetate) as solvent. The cross-linked PVP insulation films were also prepared by addition of poly (melamine-co-formaldehyde) as thermal hardener. The leakage current of the cross-linked PVP films was found to be about 300 pA with low current noise. and showed better property in electrical properties as compared with the co-polymer PVP insulation films. In addition, cross-linked PVP insulation films showed better surface morphology (roughness), showing about 0.11${\~}$0.18 nF in capacitance for all PVP film samples.

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A Study on Port Improvement with the Activation of Cross-Border E-Commerce: A Study of Pyeongtaek Port

  • Choi, Hyuk-Jun;Jung, Hyun-Jae;Lee, Dong-Hyon
    • Journal of Korea Trade
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    • v.23 no.7
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    • pp.34-44
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    • 2019
  • Purpose - The purpose of this study is to present what the port of Pyeongtaek, the hub of Korean trade with China, should improve in the current situation, wherein the e-commerce trade volume between Korea and China is increasing due to the development of online technology. Design/methodology - In this study, through prior research and expert interviews on e-commerce and port activation between borders, we derived the main improvement factors for 1) Administration and Systems, 2) Facilities, 3) Transport, and 4) Manpower, and selected 12 detailed variables for the major improvement factors. To identify the relative importance of the major improvement factors, the Analytic Hierarchy Process (AHP) method was applied, and a survey was conducted among 15 related experts. Findings - As a result, among the 12 detailed variables, Composition of Association (0.267) was the first factor to be improved, followed by Incentive Support (0.143) and E-Commerce Cluster (0.131). Based on these analyses, the main implications of this study are, first, in the current situation where the cross-border e-commerce market is growing, Pyeongtaek Port needs to form a consultative body among the government, local governments, and related businesses in connection with cross-border e-commerce and develop various support policies for the e-commerce market. Second, it will have to be able to provide differentiated services from competing ports by establishing e-commerce market-oriented clusters. Originality/value - In existing related studies, various improvements were presented to revitalize trade in line with the growth of the cross-border e-commerce market. However, with regard to most cross-border e-commerce businesses, one-dimensional improvement measures, such as improvement of payment systems, improvement of customs clearance services, and promotion of human resources, are presented in a piecemeal manner. In other words, none of the studies have proposed the importance and priority of each measure in terms of both the forward-looking and efficient allocation of resources, which is the purpose of this study. Therefore, this study contributed politically, practically, and academically by presenting countermeasures for ports to revitalize cross-border e-commerce and presenting strategic priorities using quantitative analysis methods.

A Novel Disturbance Observer Design for Dynamic Systems (동적 시스템을 위한 새로운 외란 관측기 설계)

  • Sho, Jae-Hyuk;Chung, Chung-Choo
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.388-391
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    • 2003
  • Disturbance observer(DOB) is effective to enhance the performance of system in the presence of disturbances. Various types of disturbance observer have been proposed to improve sensitivity function of system. However, it has been observed that current DOBs tend to bring poor transient response due to cross-couplings. This paper proposes a new type of disturbance observer to reduce effect of cross-couplings and provide simpler structure than Dual DOB. Finally, we verify the performance of the proposed DOB through numerical simulations.

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Abusive Language in Chinese and English

  • Zeng, Jinwen;Odhiambo, Calvin;Marlow, David
    • Cross-Cultural Studies
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    • v.28
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    • pp.141-161
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    • 2012
  • Abusive language used by college students reflects current social attitudes and values. Adopting a comparative and cross-cultural perspective, this study examines the frequency and perceived severity of abusive language in English and Mandarin Chinese. Because abusive language often includes sexual connotations, this paper employs a particular concentration on sexism. Gender differences in the use of abusive language illustrate a male bias across cultures.

Prediction of scour around single vertical piers with different cross-section shapes

  • Bordbar, Amir;Sharifi, Soroosh;Hemida, Hassan
    • Ocean Systems Engineering
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    • v.11 no.1
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    • pp.43-58
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    • 2021
  • In the present work, a 3D numerical model is proposed to study local scouring around single vertical piers with different cross-section shapes under steady-current flow. The model solves the flow field and sediment transport processes using a coupled approach. The flow field is obtained by solving the Unsteady Reynolds Averaged Navier-Stokes (URANS) equations in combination with the k-ω SST turbulence closure model and the sediment transport is considered using both bedload and suspended load models. The proposed model is validated against the empirical measurements of local scour around single vertical piers with circular, square, and diamond cross-section shapes obtained from the literature. The measurement of scour depth in equilibrium condition for the simulations reveal the differences of 4.6%, 6.7% and 13.1% from the experimental measurements for the circular, square, and diamond pier cases, respectively. The model displayed a remarkable performance in the prediction of scour around circular and square piers where horseshoe vortices (HSVs) have a leading impact on scour progression. On the other hand, the maximum deviation was found in the case of the diamond pier where HSVs are weak and have minimum impact on the formation of local scour. Overall, the results confirm that the prediction capability of the present model is almost independent of the strength of the formed HSVs and pier cross-section shapes.

System Construction Method of Parallel Operation System constructed with Three Electric Power Converters

  • Ishikura, Keisuke;Inaba, Hiromi;Kishine, Keiji;Nakai, Mitsuki;Ito, Takuma
    • Journal of international Conference on Electrical Machines and Systems
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    • v.3 no.4
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    • pp.451-457
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    • 2014
  • Parallel operation systems have an advantage in that they can be constructed quickly and inexpensively by combining existing electric power converters. However, in this case, there is a peculiar problem in that a cross current flows between the electric power converters. To design a control system more simply and commonalize the core of combination reactors, we reviewed a system construction method for parallel operation systems constructed with three electric power converters.

Identification of linearly unstable modes in the near-Earth current disruption

  • Mok, Chin-Ook;Ryu, Chang-Mo
    • Bulletin of the Korean Space Science Society
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    • 2009.10a
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    • pp.44.1-44.1
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    • 2009
  • Identification of wave characteristics during current disruption events in the near-Earth geomagnetic tail region (~ 10 RE) is important to understand the substorm onset mechanism. In this paper, linear stability analysis in the ion-cyclotron grequency range, considering temperature anisotropy and cross-field flow is presented. It is found that the ion-cyclotron drift waves propagating in a quasi-perpendicular direction with respect to the ambient magnetic field are characterized by low frequencies ($\omega$ < $0.5{\Omega}ci$), while quasi-parallel waves have frequencies close to the ion-cyclotron frequency ($\omega{\sim}{\Omega}ci$). This finding is consistent with the observation by THEMIS spacecraft of a current disruption event in which a similar high- and low-frequency band structure is also present [A. T. Y. Lui, et al., J. Geophys. Res. 113, A00C06 (2008)]. It is also found that the quasi-perpendicular mode is excited by the ion cross-field flow.

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Current Carrying Iron Whiskers: A New Magnetic Configuration

  • Lee, J.G.;Arrott, A.S.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.372-375
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    • 1995
  • The magnetization pattern of the central cross section deduced from the ac susceptibility measurement is described with an analytical function. The function is based on a charge-free configuration. The thickness of the $^{\circ}$ wall lying in a (100) plane and the wall energy are calculated analytically. Total energy of the domain structure has been minimized with Ritz's method. As the result of the minimization, the energy density of the $^{\circ}$ wall lying in a (100) plane is $0.58\;erg/cm^{2}$ and the one for a (110) plane is $1.18\;erg/cm^{2}$. Thicknesses of these walls are calculated numerically. Also, the calculation indicates there is a small central domain at the cross section without applied current. With the ac susceptibility measurement the existence of the domain without current can be identified.

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On Zinoviev's Homo Sovieticus (지노비요프의 호모 소비에티쿠스론(論) 읽기)

  • Sim, Jieun
    • Cross-Cultural Studies
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    • v.21
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    • pp.87-111
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    • 2010
  • This research examines the concept of 'homo sovieticus' by reviewing the sociological essay novel homo sovieticus written by Zinoviev who was one of the well-known dissident in Soviet Union period, and attempts to have critical understanding of the concept. It is an interesting research topic that current Russia and Russians who get through the historical layers from Soviet to post-Soviet regime at the time current trend that allows to have various academic discussions of post-Soviet. It is required to examine the past of Russia and Russian to make precise estimation of their current and future. Therefore, it is necessary to re-examine the term of 'homo sovieticus' which is conventionally accepted. This research aims at broad comprehension of homo-sovieticus by focusing on the Zinoviev's own understanding instead of the habitual use of the term which only contains ideological and political intention.

Design and Analysis of a NMOS Gate Cross-connected Current-mirror Type Bridge Rectifier for UHF RFID Applications (UHF RFID 응용을 위한 NMOS 게이트 교차연결 전류미러형 브리지 정류기의 설계 및 해석)

  • Park, Kwang-Min
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.45 no.6
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    • pp.10-15
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    • 2008
  • In this paper, a new NMOS gate cross-connected current-mirror type bridge rectifier for UHF RFID applications is presented. The DC converting characteristics of the proposed rectifier are analyzed with the high frequency equivalent circuit and the gate capacitance reduction technique for reducing the gate leakage current due to the increasing of operating frequency is also proposed theoretically by circuitry method. As the results, the proposed rectifier shows nearly same DC output voltages as the existing NMOS gate cross-connected rectifier, but it shows the gate leakage current reduced to less than 1/4 and the power consumption reduced more than 30% at the load resistor, and it shows more stable DC supply voltages for the valiance of load resistance. In addition, the proposed rectifier shows high enough and well-rectified DC voltages for the frequency range of 13.56MHz HF(for ISO 18000-3), 915MHz UHF(for ISO 18000-6), and 2.45 GHz microwave(for ISO 18000-4). Therefore, the proposed rectifier can be used as a general purpose one to drive RFID transponder chips on various RFID systems which use specified frequencies.