• Title/Summary/Keyword: Linear Simulation Method

Search Result 1,776, Processing Time 0.033 seconds

Effect on characteristics of thrust forte using arc type tester in linear induction motor (선형 유도 전동기의 회전형 시험기가 추력 특성에 미치는 영향)

  • Ham, Sang-Hwan;Lee, Sung-Gu;Lee, Hyung-Woo;Lee, Ju
    • Proceedings of the KSR Conference
    • /
    • 2009.05a
    • /
    • pp.1661-1666
    • /
    • 2009
  • This paper is analyzed the effect on characteristics of thrust force of linear induction motor(LIM) by arc type tester. Many kinds of tester have a rotational shape because of a finite length of railroad. Whereas effects by using rotational type tester are generally unknown. For reason of that, this paper is analyzed the effect on characteristics by rotational type tester using 2D finite element method(FEM), and then is compared a thrust force between linear type tester and rotational type tester. Analysis model is decided by numerical modeling for fitting the LIM for propulsion system of light rail, and it is changed to proper arc model. And then we analyzed the arc and the linear model. Consequently, arc type tester is not only useful experiment but also efficient simulation method, and small error is occurred between linear and arc model.

  • PDF

Parameters estimation of the generalized linear failure rate distribution using simulated annealing algorithm

  • Sarhan, Ammar M.;Karawia, A.A.
    • International Journal of Reliability and Applications
    • /
    • v.13 no.2
    • /
    • pp.91-104
    • /
    • 2012
  • Sarhan and Kundu (2009) introduced a new distribution named as the generalized linear failure rate distribution. This distribution generalizes several well known distributions. The probability density function of the generalized linear failure rate distribution can be right skewed or unimodal and its hazard function can be increasing, decreasing or bathtub shaped. This distribution can be used quite effectively to analyze lifetime data in place of linear failure rate, generalized exponential and generalized Rayleigh distributions. In this paper, we apply the simulated annealing algorithm to obtain the maximum likelihood point estimates of the parameters of the generalized linear failure rate distribution. Simulated annealing algorithm can not only find the global optimum; it is also less likely to fail because it is a very robust algorithm. The estimators obtained using simulated annealing algorithm have been compared with the corresponding traditional maximum likelihood estimators for their risks.

  • PDF

Longitudinal Flight Control of a Transport Aircraft Using Thrust Only

  • Ochi, Y.;Kanai, K.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.148.3-148
    • /
    • 2001
  • This paper deals with a problem of decreasing the airspeed and the altitude of a transport aircraft using thrust only. Such a situation can occur, if the aircraft loses all hydraulic power that drives the control surfaces. A controller for flight path angle control is designed using the model following servo control method, which is a PI-type optimal regulator. For computer simulation, a simulation model that covers a range of flight envelope is made using given linear models and trim points at some flight conditions. Nondimensional aerodynamic coefficients, derivatives and trim points that are not at the given trim points are computed by linear interpolation. The model is effective in simulation where the trim point varies. Simulation using ...

  • PDF

Development of Simulation Program for Multi-Air conditioner (멀티에어컨의 성능해석 프로그램 개발)

  • Jeong, B.Y.;Koh, J.Y.;Park, B.D.;Yim, C.S.
    • Solar Energy
    • /
    • v.20 no.1
    • /
    • pp.63-72
    • /
    • 2000
  • In this study, theoretical simulation method for the steady state characteristics of a refrigeration cycle which consists of one condenser and multi-evaporator (Multi-air conditioner) is presented. The simulation was performed for a typical multi-air conditioning system consisted one outdoor unit with air-cooled condenser, compressor, linear electric expansion valve and bypass circuit and connected three-evaporators (three indoor units). The simulation results are good agreement with those of experiments within 5 $\sim$ 10% at the given system operation conditions which are condensing pressure, evaporating pressure, sub-cooled degree of condenser, superheated degree, discharge temperature of compressor and pulse of linear electric expansion valve.

  • PDF

A Z-map Update Method for Linearly Moving tools (직선 운동하는 공구에 대한 Z-맵의 갱신 방법)

  • 맹승렬;백낙훈;신성용;최병규
    • Korean Journal of Computational Design and Engineering
    • /
    • v.7 no.4
    • /
    • pp.219-232
    • /
    • 2002
  • In numerically controlled(NC) machining simulation, a Z-map has been used frequently for representing a workpiece. Since the Z-map is usually represented by a set of Z-axis aligned vectors, the machining process can be simulated through calculating the intersection points between the vectors and the surface swept by a machining tool. In this paper, we present an efficient method to calculate those intersection points when an APT-type tool moves along a linear tool path. Each of the intersection points can be expressed as the solution of a system of non-linear equations. We transform this system of equations into a single-variable equation, and calculate the candidate interval in which the unique solution exists. We prove the existence of a solution and its uniqueness in this candidate interval. Based on these characteristics, we can effectively apply numerical methods to finally calculate the solution of the non-linear equations within a given precision. The whole process of NC simulation can be achieved by updating the Z-map properly. Our method can provide more accurate results with a little more processing time, in comparison with the previous closed-form solution.

Efficient Solving Methods Exploiting Sparsity of Matrix in Real-Time Multibody Dynamic Simulation with Relative Coordinate Formulation

  • Choi, Gyoojae;Yoo, Yungmyun;Im, Jongsoon
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.8
    • /
    • pp.1090-1096
    • /
    • 2001
  • In this paper, new methods for efficiently solving linear acceleration equations of multibody dynamic simulation exploiting sparsity for real-time simulation are presented. The coefficient matrix of the equations tends to have a large number of zero entries according to the relative joint coordinate numbering. By adequate joint coordinate numbering, the matrix has minimum off-diagonal terms and a block pattern of non-zero entries and can be solved efficiently. The proposed methods, using sparse Cholesky method and recursive block mass matrix method, take advantages of both the special structure and the sparsity of the coefficient matrix to reduce computation time. The first method solves the η$\times$η sparse coefficient matrix for the accelerations, where η denotes the number of relative coordinates. In the second method, for vehicle dynamic simulation, simple manipulations bring the original problem of dimension η$\times$η to an equivalent problem of dimension 6$\times$6 to be solved for the accelerations of a vehicle chassis. For vehicle dynamic simulation, the proposed solution methods are proved to be more efficient than the classical approaches using reduced Lagrangian multiplier method. With the methods computation time for real-time vehicle dynamic simulation can be reduced up to 14 per cent compared to the classical approach.

  • PDF

A Study on the Determination of Linear Model and Linear Control of Biped Robot (이족로봇의 선형모델결정과 제어에 관한 연구)

  • Park, In-Gyu;Kim, Jin-Geol
    • Proceedings of the KIEE Conference
    • /
    • 2000.11d
    • /
    • pp.765-768
    • /
    • 2000
  • Linearization of the biped dynamic equations and design of linear controller for the linearized equations are studied in this paper. The biped robot with inverted pendulum type trunk, used to stabilize the dynamic balancing of the biped robot during dynamic walking period, is modelled with 14 DOF and simulated. Despite of well defined linear control theories so far, the linear control methods was limited to the applications for a walking robot, because they have been inherently strong nonlinear properties, such as a modeling parameter uncertainties, external forces as noise, inertial and Coriolis terms by three dimensional modeling and so on. To linearize the nonlinear equations of motion of biped robot on MIMO and time varying linear equations of motion, 1st order Taylor series is used to formulate the linear equation. And a 2nd order numerical perturbation method Is used to approximate partial differential equations. Using the linearized equations of motion, a linear controller is designed by pole placement method with feed forward compensation. Using the obtained linearized equations and linear controller, the continuous walking simulation is performed.

  • PDF

Estimation of slope , βusing the Sequential Slope in Simple Linear Regression Model

  • Choi, Yong;Kim, Dongjae
    • Communications for Statistical Applications and Methods
    • /
    • v.10 no.2
    • /
    • pp.257-266
    • /
    • 2003
  • Distribution-free estimation methods are proposed for slope, $\beta$ in the simple linear regression model. In this paper, we suggest the point estimators using the sequential slope based on sign test and Wilcoxon signed rank test. Also confidence intervals are presented for each estimation methods. Monte Carlo simulation study is carried out to compare the efficiency of these methods with least square method and Theil´s method. Some properties for the proposed methods are discussed.

Adaptive Two Dimensional Linear Prediction Algorithm For Estimating Incident Angles of Multiple Broadbamd Signals. (다수의 광대역 신호의 입사각 추정을 위한 이차원의 정응선형예측 알고리즘)

  • 김태원
    • Proceedings of the Acoustical Society of Korea Conference
    • /
    • 1987.11a
    • /
    • pp.61-65
    • /
    • 1987
  • An algorithm for estimating incident angles of multiple broaband signals is proposed. The method adopts semicausal model for two dimensional linear prediction filter coefficients such that the arithmatic averag of the mean squared values of the forward and reverse prediction arrors is minimized. Preliminary results demonstrating the performance of the proposed method are presented. Simulation results indicate that the performance depends on signal-to-noise ratio and prediction order in spatial demension.

  • PDF