• 제목/요약/키워드: square root

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엔드밀 공정에서의 신호처리에 따른 제어모델에 관한 연구 (Study on Control Model Based on Signal Processing In End-Milling Process)

  • 양우석;이건복
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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    • pp.192-196
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    • 2001
  • This work describes the modeling of cutting process for feedback control based on signal processing in end-milling. Here, cutting force is used to design control model by a variety of schemes which are moving average, ensemble average, peak value, root mean square and analog low-pass filtering. It is expected that each model offers its own peculiar advantage in following cutting force control.

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THE LIMITING SPECTRAL DISTRIBUTION FUNCTION OF LARGE DIMENSIONAL RANDOM MATERICES OF SAMPLE COVARIANCE TYPE

  • Choi, Sang-Il
    • Journal of applied mathematics & informatics
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    • 제5권2호
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    • pp.465-474
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    • 1998
  • Results on the analytic behavior to the limiting spectral distribution of matrices of sample convariance type. studied in Marcenko and Pastur [2] are derived. using the Stieltjes transform it is shown that the limiting distrbution has a continuous derivative away from zero the derivative being analytic whenever it is positive and the behavior of it resembles the behavior of a square root function near the boundary of its support.

평면연삭시 복합검출방법에 의한 숫돌마멸 예측 (Prediction of Wheel Wear when Surface Grinding by Dual Detection Methods)

  • 왕덕현
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 1998년도 춘계학술대회 논문집
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    • pp.172-177
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    • 1998
  • An experimental study on the prediction of grinding wheel wear by dual detection methods was conducted by the laser displacement and acoustic emission(AE) system. The laser displacement sensor was located above the head of the grinding wheel and the AE sensor was set under the workpiece, where the wheel were condition can be detected. It was found that the dual detection methods by laser displacement system and AE system made it possible to predict the wheel wear. From the experiments, the root mean square(RMS) values both methods was found to be proportional to the grinding wheel wear.

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Fuzzy logic approach for estimating bond behavior of lightweight concrete

  • Arslan, Mehmet E.;Durmus, Ahmet
    • Computers and Concrete
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    • 제14권3호
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    • pp.233-245
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    • 2014
  • In this paper, a rule based Mamdani type fuzzy logic model for prediction of slippage at maximum tensile strength and slippage at rupture of structural lightweight concretes were discussed. In the model steel rebar diameters and development lengths were used as inputs. The FL model and experimental results, the coefficient of determination R2, the Root Mean Square Error were used as evaluation criteria for comparison. It was concluded that FL was practical method for predicting slippage at maximum tensile strength and slippage at rupture of structural lightweight concretes.

칼만필터의 최근 동향 및 발전 (Advanced Kalman filter - a survey)

  • 이장규;이연석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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    • pp.464-469
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    • 1987
  • The Kalman filter is an optimal linear estimator that has been an active research topic for the past three decades. The scheme has become the milestone of modern filtering, and it is applied to many areas including navigations and controls of free vehicle. The Kalman filter technique is matured. But some problems are still remained to be resolved. The prevention of divergence induced by digital implementation, nonoptimal application for nonlinear system, and application to non-Gaussian processes are some of the problems. This paper surveys the problems. The square root filtering is suggested to prevent the divergence. The extended Kalman filter is used for nonlinear systems. And, many other approaches to Kalman-like optimal estimators are also investigated.

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수정된 ESPRIT 방법을 이용한 다단 정현파의 주파수 추정 (Estimation in Frequencies of Multiple Sinusoids by the Modified ESPRIT Method)

  • 안태천;황금찬
    • 대한전자공학회논문지
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    • 제26권9호
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    • pp.1453-1461
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    • 1989
  • The modified ESPRIT(MESPRIT) method for harmonic retrieval is presented and analyzed. The estimation of frequencies of sinusoidal signals corrupted by white or colored measurement noise is considered for the MESPRIT method. Monte-carlo simulations are conducted for the comparison of MESPRIT method with TK method in terms of sampled mean, root mean square and relative bias.

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ANALYSIS OF THE BEHAVIOR OF LIMITING SPECTRAL DENSITY FUNCTION OF LARGE DIMENSIONAL RANDOM MATRICES

  • Choi, Sang-Il
    • Journal of applied mathematics & informatics
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    • 제16권1_2호
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    • pp.483-488
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    • 2004
  • Results on the analytic behavior of the limiting spectral distribution of large dimensional random matrices, studied in Marcenko and Pastur [2], are derived. Using the Stieltjes transform, it is shown that the limiting distribution has a continuous derivative away from zero, the derivative being analytic whenever it is positive [3]. In the present paper, it is derived that the behavior of it resembles the behavior of a square root function near the boundary of its support.

숫돌 형상 변화에 따른 연삭가공 특성에 관한 연구 (A Study on the Characteristics of Grinding due to the Different Shape of Wheel)

  • 강신엽;왕덕현;김원일;이윤경
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1996년도 추계학술대회 논문집
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    • pp.56-60
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    • 1996
  • An experimental study on the grinding temperature and Acoustic Emission(AE) signals due to the different shapes of wheel was conducted. The grinding characteristics by slotted shapes of wheel changed by width and helical angle, were compared with those by general one. Lower grinding temperature was obtained for 30$^{\circ}$ helical angle with 10mm width, Root Mean Square(RMS) values of AE signals were higher for slotted wheel rather than general one.

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An Edge-detecting Bayesian Image Reconstruction for Positron Emission Tomography

  • Um, Jong-Seok;Choi, Byong-Su
    • Communications for Statistical Applications and Methods
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    • 제4권3호
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    • pp.817-825
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    • 1997
  • Images reconstructed with EM algorithm have been observed to have checkerboard effects and have large distortions near edges as iterations proceed. We suggest a aimple algorithm of applying line process to the EM and Bayesian EM to reduce the distortions near edges. We show by simulation that this algorithm improves the clarity of the reconstructed image and has good properties based on root mean square error.

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