• 제목/요약/키워드: inverse

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

  • 김도현;신중호;김종수;김상진
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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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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High Power 전달을 위한 새로운 Inverse Pinch Switch에 관한 연구 (A Study on New Inverse Pinch Switch for High Power Transfer)

  • 조국희;김영배
    • 조명전기설비학회논문지
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    • 제20권10호
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    • pp.120-125
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    • 2006
  • Inverse pinch 스위치는 기존 스위치와 달리 전극의 손상을 줄이기 위해 나선형 전극형태로 제작하였다. 이 스위치는 전기적 트리거 펄스전압을 인가하여 동작시키며, 본 연구의 실험결과 전극간에 발생되는 아크확산 및 전류이동 때문에 전극수명이 길고, 대전류에도 견디기 때문에 펄스파워 시스템에 사용할 수 있다는 것을 확인하였다.

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

  • 김훈규;조정연
    • 천문학회보
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    • 제36권2호
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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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여유 자유도 로봇의 역기구학에 관한 연구 (An Inverse Kinematics of Redundant Manipulators)

  • 조동권;성영휘;정명진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 A
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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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    • 제23권6호
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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.

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

  • 김기완;김동민;백승욱
    • 대한기계학회논문집B
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    • 제30권3호
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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.

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

  • 김병호
    • 한국지능시스템학회:학술대회논문집
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    • 한국지능시스템학회 2007년도 추계학술대회 학술발표 논문집
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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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    • 제28권1_2호
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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
    • 대한수학회보
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    • 제40권4호
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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.

Classification Using Sliced Inverse Regression and Sliced Average Variance Estimation

  • Lee, Hakbae
    • Communications for Statistical Applications and Methods
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    • 제11권2호
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    • pp.275-285
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    • 2004
  • We explore classification analysis using graphical methods such as sliced inverse regression and sliced average variance estimation based on dimension reduction. Some useful information about classification analysis are obtained by sliced inverse regression and sliced average variance estimation through dimension reduction. Two examples are illustrated, and classification rates by sliced inverse regression and sliced average variance estimation are compared with those by discriminant analysis and logistic regression.