• Title/Summary/Keyword: Inverse

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A Study on the Modified Inverse Chebyshev Function to Realize the Passive Doubly-Terminated Ladder Network for the Even Order (우수 차수에서 수동 목종단 제자형 회로 실현이 가능한 변형된 inverse Chebyshev 함수에 관한 연구)

  • 최석우;윤창훈;김동용
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.5
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    • pp.88-94
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    • 1994
  • Inverse Chebyshev function can realize the same order of Chebyshev function nuder the same specification. In general, inverse Chebyshev function has the preferable characteristics in terms of the delay characteristics and the time-domain performances compare with Chebyshev function. However, for the even order n, inverse Chebyshev function does not realize in the doubly-terminated ladder network which has preferable sensitivity characteristics because of the finite value at ${\omega}={\infty}$. In this paper, the modified inverse Chebyshev function with $\mid$H($j^{\infty}$$\mid$=0 s proposed to realize the passive doubly-terminated ladder network for the n even or odd. The modified inverse Chebyshev function characteristics ars studied in the frequency and time domain, and then, realize the passive doubly-terminated ladder network.

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A Study on Design Approach of Inverse Cam Mechanism (Inverse Cam Mechanism 설계에 관한 연구)

  • 김도현;신중호;김종수;김상진
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.10a
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    • pp.916-919
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    • 2002
  • Cam mechanism is one of the common devices used in lots of automatic machinery. This paper introduces to an inverse cam mechanism. The inverse cam mechanism has a reverse structure as compared with common cam mechanism. For shape design of the inverse cam the approach used in this paper is an instant velocity center method that find the contact point between cam and roller at any contact time. And a computer program is developed for shape design and simulation by visual $C^{++}$ language. As the results, this paper presents two examples for the shape design of the inverse cam mechanism in order to prove the accuracy of the design procedures.

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A Study on New Inverse Pinch Switch for High Power Transfer (High Power 전달을 위한 새로운 Inverse Pinch Switch에 관한 연구)

  • Cho, Kook-Hee;Kim, Young-Bae
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.10
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    • pp.120-125
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    • 2006
  • In contrast to the conventional trigatron switch in which the currents are constricted by the z-pinch mechanical the new switch operates in an inverse pinch geometry formed by a pair of spiral electrodes in a sealed-off type. Inverse pinch switch greatly reduces hot spot formations and protects the electrode surfaces. The switch can be initiated with an electrical trigger electrode. Advantages of the new switch over the conventional switches are longer useful life, high current capability and lower inductance due to the dispersed and moving current sheet. These improved characteristics may make the inverse pinch switch suitable for pulse power systems.

INVERSE ENERGY CASCADE AND MAGNETIC HELICITY IN 3-DIMENSIONAL DRIVEN ELECTRON MAGNETOHYDRODYNAMIC TURBULENCE

  • Kim, Hoon-Kyu;Cho, Jun-Hyeon
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.2
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    • pp.112.1-112.1
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    • 2011
  • We present numerical simulations of inverse energy cascade and in driven three-dimensional (3D) electron magnetohydrodynamic (EMHD) turbulence. It has been known that inverse energy cascade only occurs in two-dimensional (2D) turbulence. However, we demonstrate that inverse energy cascade occurs in 3D driven EMHD turbulence. When magnetic helicity is injected on a small-scale, magnetic energy goes up to larger scales. The energy spectrum clearly shows inverse energy cascade. At the same time, magetic helicity spectrum also shows that the helicity goes up to larger scales. We obviously confirm inverse energy cascade. Net magnetic helicity for scales larger than the driving scale shows linear growth, and magnetic energy shows non-linear growth. On the other hand, when we drived turbulence without magnetic helicity, we do not observe inverse energy cascade.

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An Inverse Kinematics of Redundant Manipulators (여유 자유도 로봇의 역기구학에 관한 연구)

  • Cho, Dong-Kwon;Sung, Young-Hwee;Chung, Myung-Jin
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.399-402
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    • 1993
  • In this paper, an inverse kinematics of redundant manipulators is proposed. Optimality-constraint based inverse kinematic algorithms have some problems because those algorithms are based on necessary conditions for optimality. Among the problems, switching from a maximum value to a minimum value may occur and make an inverse kinematic solution unstable while performing a given task. An inverse kinematic solution for protecting from the switchings is suggested. By sufficient conditions for optimality, the configuration space is defined as a set of regions, potentially good configuration region and potentially bad configuration region. Inverse kinematics solution within potentially good configuration region can provide joint trajectories without both singularities and switchings. Through a simulation of tracing a circle, we show the effectiveness of this inverse kinematics.

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Modified inverse moment estimation: its principle and applications

  • Gui, Wenhao
    • Communications for Statistical Applications and Methods
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    • v.23 no.6
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    • pp.479-496
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    • 2016
  • In this survey, we present a modified inverse moment estimation of parameters and its applications. We use a specific model to demonstrate its principle and how to apply this method in practice. The estimation of unknown parameters is considered. A necessary and sufficient condition for the existence and uniqueness of maximum-likelihood estimates of the parameters is obtained for the classical maximum likelihood estimation. Inverse moment and modified inverse moment estimators are proposed and their properties are studied. Monte Carlo simulations are conducted to compare the performances of these estimators. As far as the biases and mean squared errors are concerned, modified inverse moment estimator works the best in all cases considered for estimating the unknown parameters. Its performance is followed by inverse moment estimator and maximum likelihood estimator, especially for small sample sizes.

Inverse Boundary Temperature Estimation in a Two-Dimensional Cylindrical Enclosure Using Automatic Differentiation and Broyden Combined Method (자동미분법과 Broyden 혼합법을 이용한 2차원 원통형상에서의 경계온도 역추정)

  • Kim Ki-Wan;Kim Dong-Min;Baek Seung-Wook
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.3 s.246
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    • pp.270-277
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    • 2006
  • Inverse radiation problems were solved for estimating boundary temperature distribution in a way of function estimation approach in an axisymmetric absorbing, emitting and scattering medium, given the measured radiative data. In order to reduce the computational time fur the calculation of sensitivity matrix, automatic differentiation and Broyden combined method were adopted, and their computational precision and efficiency were compared with the result obtained by finite difference approximation.. In inverse analysis, the effects of the precision of sensitivity matrix, the number of measurement points and measurement error on the estimation accuracy had been inspected using quasi-Newton method as an inverse method. Inverse solutions were validated with the result acquired by additional inverse methods of conjugate-gradient method or Levenberg-Marquardt method.

Inverse Kinematics of Robot Fingers with Three Joints Using Neural Network (신경회로망을 이용한 3관절 로봇 손가락의 역기구학)

  • Kim, Byeong-Ho
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2007.11a
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    • pp.159-162
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    • 2007
  • The inverse kinematics problem in robotics is an essential work for grasping and manipulation tasks by robotic and humanoid hands. In this paper, an intelligent neural learning scheme for solving such inverse kinematics of humanoid fingers is presented. Specifically, a multi-layered neural network is utilized for effective inverse kinematics, where a dynamic neural learning algorithm is employed. Also, a bio-mimetic feature of general human fingers is incorporated to the learning scheme. The usefulness of the proposed approach is verified by simulations.

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INVERSE CONSTRAINED MINIMUM SPANNING TREE PROBLEM UNDER HAMMING DISTANCE

  • Jiao, Li;Tang, Heng-Young
    • Journal of applied mathematics & informatics
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    • v.28 no.1_2
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    • pp.283-293
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    • 2010
  • In this paper, inverse constrained minimum spanning tree problem under Hamming distance. Such an inverse problem is to modify the weights with bound constrains so that a given feasible solution becomes an optimal solution, and the deviation of the weights, measured by the weighted Hamming distance, is minimum. We present a strongly polynomial time algorithm to solve the inverse constrained minimum spanning tree problem under Hamming distance.

INVERSE SHADOWING FOR EXPANSIVE FLOWS

  • Lee, Keon-Hee;Lee, Zoon-Hee
    • Bulletin of the Korean Mathematical Society
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    • v.40 no.4
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    • pp.703-713
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    • 2003
  • We extend the notion of inverse shadowing defined for diffeomorphisms to flows, and show that an expansive flow on a compact manifold with the shadowing property has the inverse shadowing property with respect to the classes of continuous methods. As a corollary we obtain that a hyperbolic flow also has the inverse shadowing property with respect to the classes of continuous methods.