• Title/Summary/Keyword: calibrated equation

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Simulation of Daily Reservoir Inflow using Objective Function Based on Storage Error (저수량 오차를 목적함수로 한 저수지 일 유입량 모의)

  • 노재경
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.4
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    • pp.76-86
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    • 2000
  • The objective function of reservoir storage error was suggested to simulate daily reservoir inflow. DAWAST model, UMAX, LMAX, FC,CP, CE were calibrated. Daily reservoir inflow was imulated with calibrated parameters and reservoir storage was simulated on a daily basis. The simulated results were compared with the monthly results by Gajiyama equation and ten-day results by Tank rainfall-runoff model through equal value lines and hydrographs . DAWAST model showed the best results compared with Gajiymama equation and Tank model. Especially, DAWAST model showed a good agreement in dry periods. NEW concept using objective function of storage error was believed to be satisfactory and to be applied in estimating reservoir inflow.

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On Design of Visual Servoing using an Uncalibrated Camera in 3D Space

  • Morita, Masahiko;Kenji, Kohiyama;Shigeru, Uchikado;Lili, Sun
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1121-1125
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    • 2003
  • In this paper we deal with visual servoing that can control a robot arm with a camera using information of images only, without estimating 3D position and rotation of the robot arm. Here it is assumed that the robot arm is calibrated and the camera is uncalibrated. We use a pinhole camera model as the camera one. The essential notion can be show, that is, epipolar geometry, epipole, epipolar equation, and epipolar constrain. These play an important role in designing visual servoing. For easy understanding of the proposed method we first show a design in case of the calibrated camera. The design is constructed by 4 steps and the directional motion of the robot arm is fixed only to a constant direction. This means that an estimated epipole denotes the direction, to which the robot arm translates in 3D space, on the image plane.

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On Design of Visual Servoing using an Uncalibrated Camera and a Calibrated Robot

  • Uchikado, Shigeru;Morita, Masahiko;Osa, Yasuhiro;Mabuchi, Tesuo;Tanya, Kanya
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.23.2-23
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    • 2001
  • In this paper we deal with visual servoing that can control a robot arm with a camera using information of images only, without estimating 3D position and rotation of the robot arm. Here it is assumed that the robot arm is calibrated and the camera is uncalibrated. We use a pinhole camera model as the camera one. The essential notion can be show, that is, epipolar geometry, epipole, epipolar equation, and epipolar constrain. These play an important role in designing visual servoing. For easy understanding of the proposed method we first show a design in case of the calibrated camera. The design is constructed by 4 steps and the directional motion of the robot arm is fixed only to a constant direction. This means that an estimated epipole denotes the direction, to which the robot arm translates in 3D space, on the image plane.

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Numerical modeling of underwater explosion phenomena (수중 폭발현상에 대한 전산해석)

  • Lee Jaimin;Kuk Jeong-Hyun;Choi Kyung Young;Cho Yong Soo;Song So-young
    • 한국전산유체공학회:학술대회논문집
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    • 1998.05a
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    • pp.1-14
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    • 1998
  • Underwater explosion properties for TNT, an ideal explosive, and DXD-04, a nonideal explosive, were numerically modeled with a one-dimensional Lagrangian hydrodynamic code. The equation of state parameters for detonation products for TNT and DXD-04 were obtained from the BKW code, assuming complete reaction. Burn of TNT was modeled by using the Chapman-Jouguet(CJ) volume burn technique, a programmed-burn technique, assuming instantaneous detonation reaction. Burn of DXD-04 was modeled by using the same technique and by using the reaction rate calibrated from two-dimensional steady-state detonation experiments. The calculations for TNT reproduced the experimental peak pressure of the shock wave propagating through water with an error of $3.0\%$ and the experimental oscillation period of the bubble formed of detonation products with an error of $2.3\%$. For DXD-04, the CJ volume burn technique could not reproduce the experimental observations. When the reaction rate calibrated from two-dimensional steady-state detonation experimental data, the calculated peak pressure was slightly higher by $7.3\%$ than the experimental data, but the calculated shock profile was in good agreement. The bubble period was reproduced with an error of $1.8\%$. These results demonstrated that underwater explosion properties for an ideal explosive can be predicted by using a programmed burn technique, and that, however, those for a nonideal explosive can be predicted only when a well-calibrated reaction rate is used.

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Comparison of Hourly and Daily SWAT Results for the Evaluation of Runoff Simulation Performance (SWAT모형의 시단위 및 일단위 유출 모의성능 비교)

  • Jang, Sun Sook;Kim, Seong Joon
    • Journal of The Korean Society of Agricultural Engineers
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    • v.58 no.5
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    • pp.59-69
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    • 2016
  • This study aims to evaluate the Soil and Water Assessment Tool (SWAT) hourly hydrological modeling performance and compare it with daily SWAT modeling parameters. For the Byeolmicheon catchment ($1.17km^2$) located in the upstream of Gyeongancheon watershed and total 18 storm events measured during 3 years (2011-2013), the hourly SWAT was calibrated and validated using the Green and Ampt (G&A) infiltration equation. The determination coefficient ($R^2$) and Nash-Sutcliffe model efficiency (NSE) of hourly SWAT discharge were 0.81 and 0.73 respectively, and the most sensitive parameter was soil saturated hydraulic conductivity (SOL_K) and calibrated with the average value of 0.075 mm/hr. In addition, the hourly SWAT simulation by G&A was compared with the daily SWAT simulation by SCS-CN (Soil Conservation Service-Curve Number) method for the whole 3 years period. The houlrly G&A results showed $R^2$ and NSE of 0.71 and 0.50, and the daily SCS-CN results were 0.71 and 0.66, respectively. The SOL_K by daily SCS_CN method was calibrated at 75.5 mm/hr, 1,000 times greater than the hourly G&A method. The next sensitive parameters for the hourly simulation were lag time of lateral flow (LAT_TIME) and lag time of surface runoff (SURLAG).

Effects of the in-process calibration from IR detector for thermal diffusivity measurement by laser flash method (레이저 섬광법에 의한 열확산계수 측정시 적외검출소자에서 실시간 온도보정이 미치는 영향)

  • 이원식;배신철
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.10 no.6
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    • pp.795-802
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    • 1998
  • For measuring the thermal diffusivity by laser flash method, raw data have to be calibrated using temperature data. We have developed in-process calibration method and polynomial calibration in which thermal diffusivity can be calibrated during measuring, This method is different from existing temperature pre-process calibration method and exponential calibration having various source of error. Using this new calibration method, measurement accuracy was improved about 1∼2% compare to the value by the existing method. We also studied more accurate fitting curve as in Figure 4 was shown the result of measuring output characteristics of IR radiometer with temperature. As illustrated in data, in-process calibration method and polynomial calibration equation is proper than pre-process calibration method and exponential calibration.

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New Method of Visual Servoing using an Uncalibrated Camera and a Calibrated Robot

  • Morita, Masahiko;Shigeru, Uchikado;Yasuhiro, Osa
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.41.4-41
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    • 2002
  • In this paper we deal with visual servoing that can control a robot arm with a camera using information of images only, without estimating 3D position and rotation of the robot arm. Here it is assumed that the robot arm is calibrated and the camera is uncalibrated. Here we consider two coordinate systems, the world coordinate system and the camera coordinate one and we use a pinhole camera model as the camera one. First of all, the essential notion can be show, that is, epipolar geometry, epipole, epipolar equation, and epipolar constrain. And these plays an important role in designing visual servoing in the later chapters. Statement of the problem is giver. Provided two a priori...

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THE CALIBRATED VARIANCE ESTIMATOR UNDER THE UNIT NONRESPONSE

  • Son, Chang-Kyoon;Hong, Ki-Hak;Lee, Gi-Sung
    • Journal of applied mathematics & informatics
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    • v.8 no.3
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    • pp.975-987
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    • 2001
  • We treat the problem of variance estimation for the estimator of population total, which is derived from the calibration estimation procedure corresponding to the levels of auxiliary information under nonresponse situation. We develop the calibrated variance estimation procedure using the fact that the population total and variance as well as the sample total and variance of the auxiliary variable are known. We show that the proposed variance estimation procedure improves the $Lundst\ddot{o}rm$ and $S\ddot{a}rndal's$ (1999) procedure with respect to the variance and nonresponse bias reduction through the simulation study.

A Prediction of Shear Strength Using Arch Models in Reinforced Concrete Beams without Web Reinforcement (아치모델을 이용한 복부보강이 안된 철근 콘크리트 보의 전단강도 산정)

  • 김대중
    • Magazine of the Korea Concrete Institute
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    • v.10 no.6
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    • pp.233-240
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    • 1998
  • A rational expression, developed to predict the shear strength of reinforced concrete beams, is derived from the relationship between shear and the rate of change of bending moment along a beam coupled with experimental findings for the arch action. The proposed ultimate shear strength equation, arising from analytical premises and then calibrated with experimental data, is a similar form to the ACI 318 equation derived mainly from empirical approach. The proposed equation depends on the concrete compressive strength, amount of longitudinal steel content, and the shear span-to-depth ratio, and rationally reflects the shear resistance mechanism of combined beam action and arch action in reinforced concrete beams. The proposed equation applied to existing test data and the results were compared with those predicted by the ACI 318 equation and the Zsutty's equation.

Relative Panel Zone Strength in Seismic Steel Moment Connections for Prevention of Panel Zone Shear Buckling (내진철골모멘트접합부 패널존의 전단좌굴 방지를 위한 패널존 상대강도)

  • Kim, So-Yeon;Lee, Cheol-Ho
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.845-850
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    • 2007
  • The empirical AISC panel zone thickness provision$(t_z\geq(d_z+w_z)$/90) to prevent the cyclic shear buckling of the panel zone was proposed based on the test data of Krawinkler et al. (1971) and Bertero et al. (1973) However, no published records of the equation development or any other background information appear to be available. The calibrated finite element analysis results of this study indicated that the AISC provision was not reasonable. In this study, through including the effects of the column axial force and the aspect ratio of the panel zone, a new equation for the relative strength between the beam and the panel zone was proposed such that the proposed equation can prevent the panel zone shear buckling and reduce the potential fracture associated with the kinking of the column flanges.

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