• Title/Summary/Keyword: Collector Method

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Extracting and Characterization of the Base Resistance based on Analysis of the Equivalent Noise Circuit for Common Collector (공통컬렉터 잡음등가회로 해석에 의한 베이스저항의 추출 및 특성)

  • Gu, Hoe-U;Lee, Gi-Yeong
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.2
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    • pp.1-4
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    • 2000
  • We presented a method for extracting the base resistance r/sun bb/ based on analysis of the equivalent noise circuit for common collector. Measurements were conducted on devices with poly-emitter structure fabricated by BiCMOS process. Base resistance measurements have been performed for different base currents and structure. For low base current it is shown that the experimental data agree with theoretical expectations.

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Evaluation of the Distribution Characteristics of Airborne Chlorides by Eight-directional collection method (8방향 포집방식에 따른 대기 중 비래염분의 분포특성 평가)

  • Cho, Gyu-Hwan;Lee, Yong-Jun;Park, Dong-Cheon
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.05a
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    • pp.98-99
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    • 2014
  • The newly developed eight-directional collector was installed at five different locations in the coastal area after its functionality was verified through experiments. Based on the airborne chloride amount measured for one year, the distribution characteristics of airborne chlorides were examined by direction. In terms of direction, a large amount of airborne chlorides was collected, not only in the direction facing the coast but also in the opposite direction. The amount measured at effective three directions was 1.5 times that measured at non-effective three directions.

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Numerical Study of Cyclone Dust Collector (싸이클론 집진기의 수치해석적 연구)

  • 전영남;엄태인
    • Journal of Korean Society for Atmospheric Environment
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    • v.12 no.1
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    • pp.43-53
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    • 1996
  • Numerical simulation was performed for the 3-dimensional flow filed of gas and particle phase for cyclone dust collector. FVM(Finite Volume Method) was employed for gas phase. The flow was solved suing the k-.varepsilon. epsilon turbulence model. The particle exit at the bottom of the cone was treated as a solid wall in this model because the gas flow through the effective dust exit is usually insignificant. The major parameters considered in this study was vortex finder diameter, effective dust exit diameterm vortex finder length, inlet type for dimension performance. Particle trajectory calculations were made for three different, particle sizes of 1, 25 and 50 .mu.m. The results obtained from this study give some physical insight of dust particle collection mechanism together with the indication of the collection efficiency. The simulation results were in generally good agreement with empirical knowledge. The application of this kind of computer program looks promising as a potential tool for the design of cyclone and determination of optimum operating condition.

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A Study for Adaptability of Beach Well Intake System as a Pre-treatment Method of Seawater Desalination Plant (기술사마당_기술자료 - 해수담수화설비의 전처리방안에서 Beach Well Intake 방법의 적용성 검토)

  • Lee, Young-Kyu
    • Journal of the Korean Professional Engineers Association
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    • v.42 no.6
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    • pp.47-52
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    • 2009
  • According to increasing demand of water mainly due to the growth of population and increased water consumption, many countries either face or worry about the shortage of fresh water. Proportionately, importance and efforts of each country to develop the potable water has been gradually increasing as well. Among others, desalination of seawater has been developed to one of the solutions mainly from the middle east and other arid regions to produce large quantity of fresh water from seawater. We installed beach seawater collector wells to develop the filtered seawater supply for desalination in a refinery. We came to a conclusion that the beach seawater collector well is one of the recommendable alternatives of seawater pre-treatment for desalination applications with lower operating cost and higher efficiency.

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Adsorptive Bubble Separation of Zinc (II) Using Capric Acid as Collector (추출제로 카프르산을 사용한 아연(II)의 흡착 기포 분리)

  • Chung Hee Kwak;Chul Lee
    • Nuclear Engineering and Technology
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    • v.15 no.2
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    • pp.149-153
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    • 1983
  • The removal of zinc (II) from aqueous solutions has been studied by the adsorptive bubble separation processes such as solvent sublation and foam fractionation processes using capric acid as collector. The efficiency of the remoal process has been studied by changing the ionic strength and pH and the bubble separation method has been compared with the solvent extraction process using the capric acid dissolved in benzene as extractant.

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A Study on the SPICE Model Parameter Extraction Method for the BJT DC Model (BJT의 DC 해석 용 SPICE 모델 파라미터 추출 방법에 관한 연구)

  • Lee, Un-Gu
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.9
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    • pp.1769-1774
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    • 2009
  • An algorithm for extracting the BJT DC model parameter values for SPICE model is proposed. The nonlinear optimization method for analyzing the device I-V data using the Levenberg-Marquardt algorithm is proposed and the method for calculating initial conditions of model parameters to improve the convergence characteristics is proposed. The base current and collector current obtained from the proposed method shows the root mean square error of 6.04% compared with the measured data of the PNP BJT named 2SA1980.

Equivalent Model Parameter Extraction of SiGe Heterojunction Bipolar Transistor (SiGe Heterojunction Bipolar Transistor의 등가모델 파라미터 추출)

  • 이성현
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.49-52
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    • 2002
  • A new method is developed to extract model parameters of SiGe HBT equivalent circuit including the base impedance and base-collector junction capacitance. Using this method, all resistances and capacitances of SiGe HBT are independently determined from measured S-parameters using two-port parameter formula. This method is proposed to reduce possible errors generated from global optimization process, and its accuracy has been verified by finding good agreements between measured and modeled current / power gain up to 18 GHz.

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Soil-Vapor Survey on Soil-Remediation by EMPLEX Collector (EMPLUX Collector에 의한 토양 오염 가스 조사)

  • Kim, Jung-Sung
    • Journal of Environmental Science International
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    • v.17 no.1
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    • pp.119-128
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    • 2008
  • Laboratory analytical results of 22 sets of hydrophobic adsorbent coils containing surface soil-vapor and two soil samples collected by conventional intrusive method from each boring location at two active dry cleaning facilities in the State of Illinois, U.S.A, were presented to evaluate the performance of soil-vapor survey. The most critical factor to determine the effectiveness of soil-vapor survey is the distance from the soil-vapor sampling device to the actual contamination, which is a function of soil porosity, permeability, primary lithology, and other geological and hydrogeological site-specific parameters. Also this factor can be affected by the history of contaminant-generating operations. The laboratory analytical results in this study showed longer dry cleaning operation history (i.e., 50 years) and presence of fine sand at the beneath Site B allow the contaminants to migrate farther and deeper over a fixed time compared to Site A(i.e., 35 years and silty clay) so that the soil-vapor survey is not likely the most effective environmental site investigation method alone for Site B. However, for Site A, the soil-vapor survey successfully screened the site to identify the location reporting the highest soil concentration of chlorinated solvents.

Study on the Analysis Performance of PVT system using the Dynamic Simulation (동적 시뮬레이션을 이용한 태양광열 시스템의 성능특성 분석)

  • Kim, Sang-Yeal;Nam, Yujin
    • KIEAE Journal
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    • v.15 no.2
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    • pp.95-101
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    • 2015
  • Purpose: A photovoltaic/thermal system is a solar collector combining photovoltaic module with a solar thermal collector, which produces electricity and heat at the same time. PVT system removes heat from PV module through air or liquid that would help to raise the efficiency of the PV systems performance. Many innovative systems and products have been put forward and their quality evaluated by academics and professionals. However, even though various of PVT system were developed and several systems were applied to practical use, there have been few researches for the performance analysis using the dynamic simulation. Method: In this study, the review of recent research and development trend for PVT systems were conducted. Furthermore, in order to develop the optimum design method, the performance analysis for PVT system was conducted by a dynamic simulation. Result: In the results, it was found that the performance of PVT system significantly depends on the ambient temperature and solar radiation. Moreover, in the weather condition of Seoul, average efficiency of electricity and heat in heating season were 13.79 and 41.85%, and they in cooling season were 14.39% and 26.18%, respectively.

An Improved Extraction Method for Splitting Base-Collector Capacitance in Bipolar Transistor Equivalent Circuit Model (바이폴라 트랜지스터 등가회로 모델의 베이스-컬렉터 캐패시턴스 분리를 위한 개선된 추출 방법)

  • 이성현
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.7
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    • pp.7-12
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    • 2004
  • An improved extraction method considering ac current crowding effect is investigated to determine intrinsic ( $C_{\mu}$) and extrinsic ( $C_{\mu}$) base-collector capacitances of bipolar junction transistors separately. The drawbacks of conventional methods are pointed out, and the improved extraction equations are derived from a cutoff mode equivalent circuit with the ac crowding capacitance. The frequency response curves of modeled current and power gains using the extracted values of $C_{\mu}$ and $C_{\mu}$ have much better agreements with measured ones than those of the conventional methods, verifying the accuracy of the improved technique.