• 제목/요약/키워드: potential model

검색결과 6,763건 처리시간 0.034초

CMOS 집적회로에서 스위칭 노이즈에 의한 신호선의 전압변동 해석 및 모델링 (Signal line potential variation analysis and modeling due to switching noise in CMOS integrated circuits)

  • 박영준;김용주;어영선;정주영;권오경
    • 전자공학회논문지C
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    • 제35C권7호
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    • pp.11-19
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    • 1998
  • A signal line potential variation due to the delta-I noise was physically investigated in CMOS integrated circuits. An equivalent circuit for the noise analysis was presented. The signal line was modeled as segmented RC-lumped circuits with the ground noise. Then the equivalent circuit was mathematically analyzed. Therebvy a new signal line potential variation model due to the switching mosie was developed. Th emodel was verified with 0.35.mu.m CMOS deivce model parameters. The model has an excellent agreement with HSPICE simulation. Thus the proposed model can be dirctly employed in the industry to design the high-performance integrted circuit design as well as integrated circuit package design.

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현열 플럭스 추정에 의한 대류 혼합층 고도의 산출 (Calculation of the Convective Mixed Layer by Estimation of Sensible Heat Flux)

  • 김용국
    • 한국환경과학회지
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    • 제7권5호
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    • pp.639-645
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    • 1998
  • A Jump model was evaluated for the calculation of hourly mixing height and mean potential temperature within the height. The Sump model was modified for estimation of downward heat fluxes by mechanical convections and surface heat fluxes. The surface heat fluxes were estimated from routine weather data such as solar radiation and air temperature. Total of 8 upper-air data observed at 0000UTC and 0600UTC in Osan station during April 23 to 26, 1996 were analyzed, and compared to the model results in detail. The calculated mixing heights and potential temperatures within the height were comparable to the observations, but some differences were showed. The calculated mixing heights were generally higher than observations. And, when variations of wind directions were large, the large difference of potential temperature was occurred. From the results, it was important to note that vortical motions and advections of air masses would affect to the growth of the mixing height.

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Analysis of Transport Characteristics for FinFET Using Three Dimension Poisson's Equation

  • Jung, Hak-Kee;Han, Ji-Hyeong
    • Journal of information and communication convergence engineering
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    • 제7권3호
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    • pp.361-365
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    • 2009
  • This paper has been presented the transport characteristics of FinFET using the analytical potential model based on the Poisson's equation in subthreshold and threshold region. The threshold voltage is the most important factor of device design since threshold voltage decides ON/OFF of transistor. We have investigated the variations of threshold voltage and drain induced barrier lowing according to the variation of geometry such as the length, width and thickness of channel. The analytical potential model derived from the three dimensional Poisson's equation has been used since the channel electrostatics under threshold and subthreshold region is governed by the Poisson's equation. The appropriate boundary conditions for source/drain and gates has been also used to solve analytically the three dimensional Poisson's equation. Since the model is validated by comparing with the three dimensional numerical simulation, the subthreshold current is derived from this potential model. The threshold voltage is obtained from calculating the front gate bias when the drain current is $10^{-6}A$.

Effect of Soil Factors on Vegetation Values of Salt Marsh Plant Communities: Multiple Regression Model

  • Ihm, Byung-Sun;Lee, Jeom-Sook;Kim, Jong-Wook;Kim, Joon-Ho
    • Journal of Ecology and Environment
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    • 제29권4호
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    • pp.361-364
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    • 2006
  • The objective of the current study was to characterize and apply multiple regression model relating to vegetation values of the plant species over salt marshes. For each salt marsh community, vegetation and soil variables were investigated in the western coast and the southern coast in South Korea. Osmotic potential of soil and $Cl^-$ content of soil as independent variable had positive and negative influences on vegetation values. Multiple regression model showed that vegetation values of 14 coastal plant communities were determined by pH of soil, osmotic potential of soil and sand content. The multiple regression equation may be applied to the explanation of distribution and abundance of plant communities with exiting ordination plots.

반구형 축소모델을 이용한 접지전극 주변의 전위상승 분석 (Analysis of the Potential Rises near Grounding Electrodes using Semisplere type scale Model)

  • 이복희;백영환;이봉;김기복
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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    • pp.259-262
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    • 2008
  • This paper describes the ground surface potential profiles near the object to be grounded. The hemisphere water tank was used to simulate the. scale model. As a result, the ground surface potential near the ground electrode was considerably raised. In particular the ground surface potential at the just upper part of ground rod was higher than other part. The ground surface potential was lowered with increasing the buried depth of ground rod.

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Thermodynamic Model for Partition Coefficients in the Two Protein Systems

  • Jung, Chang-Min;Bae, Young-Chan;Kim, Jae-Jun
    • Macromolecular Research
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    • 제15권7호
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    • pp.682-687
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    • 2007
  • The equation of state developed herein is predicated on a hard-sphere reference with perturbations introduced via a potential function to account for electrostatic forces and for attraction between protein particles. During this process, the generalized Lennard-Jones (GLJ) pair potential function is employed. The GLJ pair potential function is employed to represent the protein-protein interaction in two-protein systems. Via the use of the relation between the equation of state and the chemical potential, the phase behavior in the aqueous two-protein system can be estimated. The partition coefficients can be obtained via these processes. The calculated values of the coefficients agree fairly well with the experimental data in the given pH and ionic strength range, with no additional adjustable model parameters.

Alternative Potentials Analyzing the Scattering Cross Sections of 7,9,10,11,12,14Be Isotopes from a 12C target: Proximity Potentials

  • Aygun, M.
    • Journal of the Korean Physical Society
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    • 제73권9호
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    • pp.1255-1262
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    • 2018
  • In this paper, alternative potentials to explain the scattering cross sections of $^{7,9,10,11,12,14}Be$ isotopes by a $^{12}C$ target nucleus at different energies are researched. For this purpose, fourteen different proximity potentials, such as Proximity 1966, Proximity 1976, Proximity 1977, Proximity 1979, Proximity 1984, Proximity 1988, Proximity 1995, Broglia and Winther 1991, Aage Winther, Bass 1973, Bass 1977, Bass 1980, Christensen and Winther 1976, and $Ng{\hat{o}}$ 1980, are used to produce the real potential within the optical model. The imaginary potential is formed by using the Woods-Saxon potential. The theoretical results are compared with both experimental data and data reported in the literature. The results are in good agreement with the data. The proximity potentials are observed to play a significant role in obtaining the scattering cross sections of $^{7,9,10,11,12,14}Be$ isotopes.

A Functional Representation of the Potential Energy Surface of Non-Identical $S_N2$ Reaction: F- … $CH_3Cl \rightarrow FCH_3$ … Cl-

  • 김정섭;김영훈;노경태;이종명
    • Bulletin of the Korean Chemical Society
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    • 제19권10호
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    • pp.1073-1079
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    • 1998
  • The potential energy surface (PES) of the non-identical SN2 reactions, F- + CH3Cl → FCH3 + Cl and (H2O)F + CH3Cl → FCH3 + Cl-(H2O), were investigated with ab initio MO calculations. The ab initio minimum energy reaction path (MERP) of the F- + CH3Cl → FCH3 + Cl- was obtained and it was expressed with an intermediate variable t. The ab initio PES was obtained near around t. Analytical potential energy function (PEF) was determined as a function of the t in order to reproduce the ab initio PES. Based on Morse-type potential energy function, a Varying Repulsive Cores Model (VRCM) was proposed for the description of the bond forming and the bond breaking which occur simultaneously during the SN2 reaction. The MERP calculated with the PEF is well agreed with the ab initio MERP and PEF could reproduce the ab initio PES well. The potential parameters for the interactions between the gas phase molecules in the reactions and water were also obtained. ST2 type model was used for the water.

A Novel Modulation Method for Three-Level Inverter Neutral Point Potential Oscillation Elimination

  • Yao, Yuan;Kang, Longyun;Zhang, Zhi
    • Journal of Power Electronics
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    • 제18권2호
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    • pp.445-455
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    • 2018
  • A novel algorithm is proposed to regulate the neutral point potential in neutral point clamped three-level inverters. Oscillations of the neutral point potential and an unbalanced dc-link voltage cause distortions of the output voltage. Large capacitors, which make the application costly and bulky, are needed to eliminate oscillations. Thus, the algorithm proposed in this paper utilizes the finite-control-set model predictive control and the multistage medium vector to solve these issues. The proposed strategy consists of a two-step prediction and a cost function to evaluate the selected multistage medium vector. Unlike the virtual vector method, the multistage medium vector is a mixture of the virtual vector and the original vector. In addition, its amplitude is variable. The neutral point current generated by it can be used to adjust the neutral point potential. When compared with the virtual vector method, the multistage medium vector contributes to decreasing the regulation time when the modulation index is high. The vectors are rearranged to cope with the variable switching frequency of the model predictive control. Simulation and experimental results verify the validity of the proposed strategy.

A New Two-Dimensional Model for the Drain-Induced Barrier Lowering of Fully Depleted Short-Channel SOI-MESFET's

  • Jit, S.;Pandey, Prashant;Pal, B.B.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제3권4호
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    • pp.217-222
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    • 2003
  • A new two-dimensional analytical model for the potential distribution and drain-induced barrier lowering (DIBL) effect of fully depleted short-channel Silicon-on-insulator (SOI)-MESFET's has been presented in this paper. The two dimensional potential distribution functions in the active layer of the device is approximated as a simple parabolic function and the two-dimensional Poisson's equation has been solved with suitable boundary conditions to obtain the bottom potential at the Si/oxide layer interface. It is observed that for the SOI-MESFET's, as the gate-length is decreased below a certain limit, the bottom potential is increased and thus the channel barrier between the drain and source is reduced. The similar effect may also be observed by increasing the drain-source voltage if the device is operated in the near threshold or sub-threshold region. This is an electrostatic effect known as the drain-induced barrier lowering (DIBL) in the short-gate SOI-MESFET's. The model has been verified by comparing the results with that of the simulated one obtained by solving the 2-D Poisson's equation numerically by using the pde toolbox of the widely used software MATLAB.