• Title/Summary/Keyword: material parameter extraction

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Study on the Material Parameter Extraction of the Overlay Model for the Low Cycle Fatigue(LCF) Analysis (저주기 피로해석을 위한 다층모델의 재료상수 추출에 관한 연구)

  • Kim, Sang-Ho;Kabir, S.M. Humayun;Yeo, Tae-In
    • Transactions of the Korean Society of Automotive Engineers
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    • v.18 no.1
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    • pp.66-73
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    • 2010
  • This work was focused on the material parameter extraction for the isothermal cyclic deformation analysis for which Chaboche(Combined Nonlinear Isotropic and Kinematic Hardening) and Overlay(Multi Linear Hardening) models are normally used. In this study all the parameters were driven especially based on Overlay theories. A simple method is suggested to find out best material parameters for the cyclic deformation analysis prior to the isothermal LCF(Low Cycle Fatigue) analysis. The parameter extraction was done using 400 series stainless steel data which were published in the reference papers. For simple and quick review of the parameters extracted by suggested method, 1D FORTRAN program was developed, and this program could reduce the time for checking the material data tremendously. For the application to FE code ABAQUS user subroutine for the material models was developed by means of UMAT(User Material Subroutine), and the stabilized hysteresis loops obtained by the numerical analysis were in good harmony with test results.

A Time-Domain Parameter Extraction Method for Speech Recognition using the Local Peak-to-Peak Interval Information (국소 극대-극소점 간의 간격정보를 이용한 시간영역에서의 음성인식을 위한 파라미터 추출 방법)

  • 임재열;김형일;안수길
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.2
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    • pp.28-34
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    • 1994
  • In this paper, a new time-domain parameter extraction method for speech recognition is proposed. The suggested emthod is based on the fact that the local peak-to-peak interval, i.e., the interval between maxima and minima of speech waveform is closely related to the frequency component of the speech signal. The parameterization is achieved by a sort of filter bank technique in the time domain. To test the proposed parameter extraction emthod, an isolated word recognizer based on Vector Quantization and Hidden Markov Model was constructed. As a test material, 22 words spoken by ten males were used and the recognition rate of 92.9% was obtained. This result leads to the conclusion that the new parameter extraction method can be used for speech recognition system. Since the proposed method is processed in the time domain, the real-time parameter extraction can be implemented in the class of personal computer equipped onlu with an A/D converter without any DSP board.

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Parameter Extraction for Optimum Design of Low Noise GaAs MESFET (저잡음 GaAs MESFET의 최적화 설계를 위한 파라미터 추출)

  • 이상배
    • Journal of the Korean Institute of Navigation
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    • v.16 no.3
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    • pp.65-76
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    • 1992
  • An algorithm to determine the optimum nominal value of geometrical and material parameters in divice modelling is proposed. The algorithm uses the yield and variance prediction formula and Monte-Carlo analysis. The performance specification of the noise figure must also be satisfied. In this paper, the total number of considered devices is 1000, and each parameter of geometrical and material parameters is generated randomly within the limits of ${\pm}3%$ of nominal value, and the distribution of 1000 geometrical and material parameters is gaussing distribution.

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Application of Technique Discrete Wavelet Transform for Acoustic Emission Signals (음향방출신호에 대한 이산웨이블릿 변환기법의 적용)

  • 박재준;김면수;김민수;김진승;백관현;송영철;김성홍;권동진
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.585-591
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    • 2000
  • The wavelet transform is the most recent technique for processing signals with time-varying spectra. In this paper, the wavelet transform is utilized to improved the assessment and multi-resolution analysis of acoustic emission signals generating in partial discharge. This paper especially deals with the assessment of process statistical parameter using the features extracted from the wavelet coefficients of measured acoustic emission signals in case of applied voltage 20[kv]. Since the parameter assessment using all wavelet coefficients will often turn out leads to inefficient or inaccurate results, we selected that level-3 stage of multi decomposition in discrete wavelet transform. We applied FIR(Finite Impulse Response)digital filter algorithm in discrete to suppression for random noise. The white noise be included high frequency component denoised as decomposition of discrete wavelet transform level-3. We make use of the feature extraction parameter namely, maximum value of acoustic emission signal, average value, dispersion, skewness, kurtosis, etc. The effectiveness of this new method has been verified on ability a diagnosis transformer go through feature extraction in stage of acting(the early period, the last period) .

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Distance measurement system compensated parameters for extraction of 3D distance (원거리 물체의 3차원거리 측정시의 파라미터 보정된 거리측정시스템)

  • Kim, Jeong-Man;Kim, Young-Min;Kim, Won-Sup;Hwang, Jong-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.605-606
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    • 2005
  • Depth error correction effect for maladjusted stereo cameras with calibrated pixel distance parameter is presented. Intra and extra parameters should be obtain to determine the relation between image and world coordination through experiment. One difficulty is in camera alignment for parallel installation: placing two CCD arrays in a plane. If the pixel distance parameter which is one of intra parameter is calibrated with known points, such error can be compensated in some amount. Such error compensation effect with the calibrated pixel distance parameter is demonstrated with various experimental results.

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A study on process parameter extraction and device characteristics of nMOSFET using DTC method (DTC방법을 사용한 nMOSFET의 공정파라메터 추출 및 소자특성에 관한 연구)

  • 이철인;장의구
    • Electrical & Electronic Materials
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    • v.9 no.8
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    • pp.799-805
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    • 1996
  • In short channel MOSFET, it is very important to establish optimal process conditions because of variation of device characteristics due to the process parameters. In this paper, we used process simulator and device characteristics caused by process parameter variation. From this simulation, it has been ' derived to the dependence relations between process parameters and device characteristics. The experimental result of fabricated short channel device according to the optimal process parameters demonstrate good device characteristics.

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Characteristics of Fabricated Devices and Process Parameter Extraction by DTC (DTC에 의한 공정 파라메터 추출 및 제작된 소자의 특성)

  • 서용진;이철인;최현식;김태형;최동진;장의구
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1993.11a
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    • pp.29-34
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    • 1993
  • In this paper, we used one-dimensional process simulator, SUPREM-II, and two-dimensional device simulator, MINIMOS 4.0 to extract optimal process parameter that can minimize degradation of device characteristics caused by process parameter variation in the case of short channel nMOSFET and pMOSFET device. From this simulation, we have derieved the relationship between process parameter and device characteristics. Here we have presented a method to extract process parameters from design trend curve(DTC) obtained by process and device simulations. We parameters to verify the validity of the DTC method. The experimental result of 0.8 $\mu\textrm{m}$ channel length devices that have been fabricated with optimal that reduces short channel effects, that is, good drain current-voltage characteristics, low body effects and threshold voltage of 1.0 V, high punchthrough and breakdown voltage of 12 V, low subthreshold swing(S.S) values of 105 mV/decade.

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Distribution of Zr(IV) Ion Species in Aqueous Solution (수용액(水溶液)에서 지르코늄이온의 농도분포(濃度分布))

  • Lee, Man-Seung;Lee, Hwa-Young
    • Resources Recycling
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    • v.20 no.6
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    • pp.56-62
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    • 2011
  • Zirconium is used in nuclear reactors as a structural material due to its excellent corrosion resistance and to low neutron crosssection. Variation in the distribution and solubility of Zr(IV) with solution pH was obtained. Distribution of Zr(IV) containing species in HCl and $HNO_3$ solution was analyzed by considering the complex formation of Zr(IV) species with the anion of the inorganic acid. Bromley interaction parameter between $ZrO^{2+}$ and nitrate ion was estimated by using the reported data on the solvent extraction of Zr(IV) by Cyanex272 from $HNO_3$ solution. This Bromley parameter can be utilized in calculating extraction isotherm of Zr(IV) and in predicting the separation factor between Zr(IV) and Hf(IV).