• 제목/요약/키워드: current profiles

검색결과 453건 처리시간 0.028초

ZrO$_2$ 유전체의 전기적 특성 모델링 (Modeling of ZrO$_2$ dielectric characteristics)

  • 이봉용;허광수;박민철;유정호;이동원;남서은;명재민;고대홍;윤일구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.410-413
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    • 2002
  • In this paper, the performance of high-k dielectric is modeled by observing electrical characteristics through the process and device simulation. ZrO$_2$ on Si substrate is used as test structures to characterize the current-voltage and the capacitance-voltage profiles. In order to verify the simulation results, the experimental results are used as a reference. Based on the modeling results, the methodology can be a potential tool to predict the characteristics of the ZrO$_2$ dielectric.

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2상 통전 방식에서의 PWM 방식에 따른 소음 특성 분석 (An Analysis of Noise Characteristics according to PWM Method in 2-Phase Conduction Method)

  • 오재윤;정달호;김정철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 F
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    • pp.2632-2634
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    • 1999
  • In this paper, we analyze the characteristics of Motor Noise according to PWM method, especially in the case of 2-phase conduction method. There are two types of PWM methods used usually. One is Lower-PWM and the other is Upper&Lower PWM. Because there is a difference between freewheeling path of both methods, Current profiles of two methods are different. This makes the difference of Torque Ripple and so difference of Noise Performance. In this paper, the path will be analyzed and the comparison of Noise performance of two types of PWM methods will be showed by experiment results.

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좌주간부 관상동맥(LCCA)에 관한 혈류역학적 분석 (II) (Hemodynamic Analysis of Pig's Left Common Coronary Artery (LCCA) (II))

  • 문수연;장주희;박정수;신세현
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.2043-2047
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    • 2003
  • The distributions of blood pressure, blood flow, and blow volume in the left common artery (LCCA) were determined using the lumping parameter method. In order to develop a mathematical model for microcirculation in LCCA, the present study adopted preexisted set of measured morphological data on anatomy, mechanical properties of the coronary vessels, viscosity of blood, the basic laws of physics, and the appropriate boundary condition. Pressures and volumes of blood and flow resistance were expressed in terms of electrical voltages, current, and resistances, respectively, in the electrical analog model. The results of two mathematical models, symmetrical and asymmetrical models, were compared with other investigator's data. The present results were in good agreement with previous studies. It was found that the mean pressure profiles were similar in both models.

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Vertical Temperature Profile in the Yellow Sea according to the Variations of Air Temperature

  • CHO Kyu-Dae;CHO Kwang-Woo
    • 한국수산과학회지
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    • 제21권1호
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    • pp.1-10
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    • 1988
  • The vertical temperature profiles of the Yellow Sea in summer are investigated by means of the nine air temperature (AT) patterns which are classified with the AT of winter and summer. The sea surface temperature (SST) is high when the AT of summer is high, and vice versa. The gradient of thermocline in the offshore region is higher than that in the coastal region and is not always favorable with the AT patterns. The relation between sea bottom temperature (SBT) and the AT of winter is favorable when the SBT is averaged in the coastal and offshore stations. In addition, the SST of coastal stations is higher than that of offshore stations because of the strong mixing by the tidal current in the coastal region. The correlation between the AT and the SST of August is favorable (r=0.44-0.69), while the correlation between the AT of February and the SBT of August is not favorable except the stations, A2 (r=0.57) and B2 (r=0.61).

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GSI급 MOS Transistor 개발을 위한 HEI (High-Energy Ion Implantation) 공정 분석 시뮬레이터 개발 (Development of Analysis Simulation Tool of High-Energy Ion Implantation Process for GSI MOS Transistor)

  • 손명식;박수현;이영직;권오근;황호정
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.946-949
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    • 1999
  • In this research we have developed a reliable, effective and feasible HEI(High-Energy Ion Implantation) process 3D-simulation tool, and then by using it we can predict and analyze the effect of HEI process on characteristics of the standard CMOS device. high-energy ion implantation above 200 keV is inevitable process to form retrograde well and buried layer to prevent leakage current, to conduct field implant for field isolation, and to perform after-gate implantation. The feasible analysis tool is a product of the HEI process modeling verified by comparison of the SIMS experiments with the simulation results. Especially, in this paper, we present the predicting capability of HEI-induced impurity and damage profiles compared with the published SIMS data in order to acquire the reliability of our results ranging from few keV to several MeV for phosphorus and boron implantation.

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점토의 압축성을 고려한 전단탄성계수의 정식화 방법에 대하여 (On the compressibility and elastic shear modulus of clay)

  • 황성춘;오병현;박성진
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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    • pp.91-97
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    • 2001
  • Case records comprising the results of down-hole seismic surveys collected at nine sites worldwide, together with comparative results of laboratory bender element tests on reconstituted clay samples, were examined in an attempt to quantify the shear modulus of normally consolidated clays at very small strain of the order of 0.001%. The shear modulus G$_{max}$ under the current state of stresses is given in a formula which includes a newly proposed void ratio function. An empirical expression incorporating the new void ratio function is also proposed for practical use in estimating G$_{max}$ profiles with depth in natural soil deposits from routinely available borehole data.ata.

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3차원 유한요소법에 기초한 조질 압연 공정 해석 - Part II : 모델 개발 (3D Finite Element-based Study on Skin-pass Rolling - Part II : Development of the Model)

  • 윤성진;황상무
    • 소성∙가공
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    • 제25권2호
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    • pp.136-140
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    • 2016
  • Although the finite element method is a good tool to analyze skin-pass rolling, it is hard to be applied in the field because of its long calculation time. In the current study, simple numerical models were developed for the prediction of roll force and residual stress profiles along the strip width. These models are based on finite element analysis and a coupled solution of Sims’ equation and Hitchcock’s formula. The results indicate that plastic strains can be represented as in simple equations of the deformed roll profile and the initial thickness of the strip.

VOF 방법을 이용한 GMA 용접의 금속 이행에 관한 동적 해석 (I) - 입상 용적과 스프레이 이행 모드의 해석 - (Dynamic Analysis of Metal Transfer using VOF Method in GMAW (I) - Globular and Spray Transfer Modes)

  • 최상균;유중돈;김용석
    • Journal of Welding and Joining
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    • 제15권3호
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    • pp.36-46
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    • 1997
  • Dynamics of molten drop detachment in the Gas Metal Arc (GMA) welding is investigated using the Volume of Fluid(VOF) method. The electromagnetic effects are included in the formulation of the VOF method which has been widely used to analyze the dynamics of the fluid having a free surface. The molten drop geometry, pressure and velocity profiles within the drop are calculated numerically in the cases of globular and spray transfer modes. It appears that the velocity and current distribution affect metal detachment. It is found that the taper is formed and maintained during the spray transfer by the electromagnetic force. Predicted results show reasonably good agreement with the available experimental data which validates the application of the VOF method to metal transfer analysis.

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인접블록의 상관관계에 기반한 RGB video coding 개선 알고리즘 (Enhanced RGB Video Coding Based on Correlation in the Adjacent Block)

  • 김양수;정진우;최윤식
    • 전기학회논문지
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    • 제58권12호
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    • pp.2538-2541
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    • 2009
  • H.264/AVC High 4:4:4 Intra/Predictive profiles supports RGB 4:4:4 sequences for high fidelity video. RGB color planes rather than YCbCr color planes are preferred by high-fidelity video applications such as digital cinema, medical imaging, and UHDTV. Several RGB coding tools have therefore been developed to improve the coding efficiency of RGB video. In this paper, we propose a new method to extract more accurate correlation parameters for inter-plane prediction. We use a searching method to determine the matched macroblock (MB) that has a similar inter-color relation to the current MB. Using this block, we can infer more accurate correlation parameters to predict chroma MB from luma MB. Our proposed inter-plane prediction mode shows an average bits saving of 15.6% and a PSNR increase of 0.99 dB compared with H.264 high4:4:4 intra-profile RGB coding. Furthermore, extensive performance evaluation revealed that our proposed algorithm has better coding efficiency than existing algorithms..

적응 뉴로퍼지 추론기법에 의한 SRM의 토오크모델 (Adaptive Neuro-Fuzzy Ingerence based Torque Model of SRM)

  • 홍정표;박성준;홍순일;김철우
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1999년도 학술대회논문집-국제 전기방전 및 플라즈마 심포지엄 Proceedings of 1999 KIIEE Annual Conference-International Symposium of Electrical Discharge and Plasma
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    • pp.279-284
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    • 1999
  • Although the switched reluctance motor (SRM) has a several advantages such as simple magnetic structure, robustness, wide range of speed characteristics and simple driving, it has a considerable inherent torque ripple and speed variation duet to the driving characteristics of pulse current waveform and the nonlinear inductance profile. The high torque ripple and speed variation inhibits wide application. The minimization of the torque ripple is very important in high performance servo drive applications, which require smooth operation with minimum torque pulsations. This paper presents the new SRM torque modeling technique for the control of instantaneous torque. The SRM is modeled by the database of torque profiles for every small variation in currents and rotor angles, which is inferred from the several measured data by the adaptive neuro-fuzzy inference technique. Simulation results demonstrating the effectiveness of proposed torque modeling technique are presented.

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