• 제목/요약/키워드: Salient Feature

검색결과 116건 처리시간 0.031초

A Saliency-Based Focusing Region Selection Method for Robust Auto-Focusing

  • Jeon, Jaehwan;Cho, Changhun;Paik, Joonki
    • IEIE Transactions on Smart Processing and Computing
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    • 제1권3호
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    • pp.133-142
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    • 2012
  • This paper presents a salient region detection algorithm for auto-focusing based on the characteristics of a human's visual attention. To describe the saliency at the local, regional, and global levels, this paper proposes a set of novel features including multi-scale local contrast, variance, center-surround entropy, and closeness to the center. Those features are then prioritized to produce a saliency map. The major advantage of the proposed approach is twofold; i) robustness to changes in focus and ii) low computational complexity. The experimental results showed that the proposed method outperforms the existing low-level feature-based methods in the sense of both robustness and accuracy for auto-focusing.

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PSS 정수 튜닝을 위한 전력시스템 미소신호 안정도 해석 프로그램 (Computer Analysis Program of Small-Signal Stability of Power System for Tuning PSS′s parameters)

  • 김동준;문영환;허진;신정훈;김태균;추진부
    • 대한전기학회논문지:전력기술부문A
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    • 제52권5호
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    • pp.241-249
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    • 2003
  • This paper describes a novel approach for performing eigenvalue analysis and frequency domain analysis of multi-machine power system. The salient feature of this approach is a direct approach for constructing the state matrix equations of linearized power systems about its operating point using modular technique. These state matrix equations are then used to obtain eigenvalues and mode shapes of the system, and frequency response, or Bode, plots of selected transfer functions. The proposed program provides a flexible tool for systematic analyses of tuning PSS's parameters. The paper also presents its application to the analyses of a single-machine infinite bus system and two-area system with 4 machines.

DIDF 방법을 이용한 주기성 외란의 제거 (Periodic Disturbance Cancellation by using Dual-Input Describing Function (DIDF) Method)

  • 최연욱;이형기
    • 전기학회논문지
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    • 제59권1호
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    • pp.168-175
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    • 2010
  • The issue of rejecting periodic disturbances arises in various applications dealing with rotating machinery. A new method using DIDF (Dual-Input Describing Function) is presented for the rejection of periodic disturbances with uncertain frequency. This can be added to an existing feedback control system without altering the closed-loop system stability. The objective is to design a nonlinear compensator to secure specified oscillation amplitude and frequency which are the same as disturbances. We suggest two procedures to determine coefficients for DIDF's synthesis. The structure of the proposed DIDF is so simple that we can easily synthesize. A number of computer simulations were carried out to demonstrate the salient feature of the proposed DIDF compared to the conventional ones(that is, adaptive algorithms).

A BAYESIAN ANALYSIS FOR PRODUCT OF POWERS OF POISSON RATES

  • KIM HEA-JUNG
    • Journal of the Korean Statistical Society
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    • 제34권2호
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    • pp.85-98
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    • 2005
  • A Bayesian analysis for the product of different powers of k independent Poisson rates, written ${\theta}$, is developed. This is done by considering a prior for ${\theta}$ that satisfies the differential equation due to Tibshirani and induces a proper posterior distribution. The Gibbs sampling procedure utilizing the rejection method is suggested for the posterior inference of ${\theta}$. The procedure is straightforward to specify distributionally and to implement computationally, with output readily adapted for required inference summaries. A salient feature of the procedure is that it provides a unified method for inferencing ${\theta}$ with any type of powers, and hence it solves all the existing problems (in inferencing ${\theta}$) simultaneously in a completely satisfactory way, at least within the Bayesian framework. In two examples, practical applications of the procedure is described.

TRANSFORMATION OF DIMENSIONLESS HEAT DIFFUSION EQUATION FOR THE SOLUTION OF DYNAMIC DOMAIN IN PHASE CHANGE PROBLEMS

  • Ashraf, Muhammad;Avila, R.;Raza, S. S.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제13권1호
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    • pp.31-40
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    • 2009
  • In the present work transformation of dimensionless heat diffusion equation for the solution of moving boundary problems have been formulated. The formulation is based on 1-D, 2-D and 3-D, unsteady heat diffusion equations. These equations are rst turned int dimensionless form by using dimensionless quantities and their transformation was formulated in liquid and solid phases. The salient feature of this work is that during the transformation of dimensionless heat diffusion equation there arises a convective term $\tilde{v}$ which is responsible for the motion of interface in liquid as well as solid phase. In the transformed heat equation, a correction factor $\beta$ also arises naturally which gives the correct transformed flux at interface.

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COMMODITY FUTURES TERM STRUCTURE MODEL

  • Choi, Hyeong In;Kwon, Song-Hwa;Kim, Jun Yeol;Jung, Du-Seop
    • 대한수학회보
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    • 제51권6호
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    • pp.1791-1804
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    • 2014
  • A new approach to the commodity futures term structure model is introduced. The most salient feature of this model is that, once the interest rate model is given, the commodity futures price volatility is the only quantity that completely determines the model. As a consequence this model enables one to do away with the drudgeries of having to deal with the convenience yield altogether, which has been the most thorny point so far.

Image rasterization을 위한 Edge Painting Machine의 설계 및 simulation (Design and Simulation of Edge Painting Machine for Image Rasterization)

  • 최상길;김성수;어길수;경종민
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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    • pp.1492-1494
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    • 1987
  • This paper describes a hardware architecture called Edge Painting Machine for real time generation of scan line images for raster scan graphics display. The Edge Painting Machine consists of Scanline Processor which converts polygon data sorted in their depth priority into a set of scan line commands for each scan line, and Edge Painting Tree which converts the scanline commands set into a raster line image. Edge painting tree has been designed using combinational logic circuit. The designed circuit has been simulated to verify the proper functioning. A salient feature of the EPT is that hardware composition is simple, because each processor is constituted by only combinational logic circuit.

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Moving Vehicle Segmentation from Plane Constraint

  • Kang, Dong-Joong;Ha, Jong-Eun;Kim, Jin-Young;Kim, Min-Sung;Lho, Tae-Jung
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.2393-2396
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    • 2005
  • We present a method to detect on-road vehicle using geometric invariant of feature points on side planes of the vehicle. The vehicles are assumed into a set of planes and the invariant from motion information of features on the plane segments the plane from the theory that a geometric invariant value defined by five points on a plane is preserved under a projective transform. Harris corners as a salient image point are used to give motion information with the normalized correlation centered at these points. We define a probabilistic criterion to test the similarity of invariant values between sequential frames. Experimental results using images of real road scenes are presented.

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헬름홀츠 감쇠기를 응용한 유압시스템의 유압맥동 및 소음 최소화 연구 (Hydraulic Pulsation and Noise Reduction using the Helmholtz Attenuator)

  • 김동현;이대옥;최근국
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 춘계학술대회 논문집
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    • pp.614-619
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    • 1997
  • The hydraulic pressure pulsation has on the effected on the acoustic nosie and control performance of the hydraulic-servo system. The Helmholtz attenuator introduction on the hydraulic line is an efficient device to reduce the hydraulic pulsation. The salient feature of causing hydraulic pulsation and the frequency characteristics of Helmholtz attenuator are studied. The hydraulic filter design parameters such as the locating position, connecting orifice area and accumulator volume are mathematically analyzed. The instrumental works are carried out with the remarkable reduction of the hydraulic pressure pulsation magnitude and the acoustic noise level.

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전기-유압서보에 의한 자동유압굴삭기의 개발에 관한 연구(1) -가변구조에 의한 궤도추종제어 시뮬레이션- (A study on the development of Electro-hydraulic servo Excavator(1) -Simulation of the trajectory tracking control using VSS-)

  • 허준영;하석홍;이진걸
    • 한국정밀공학회지
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    • 제6권2호
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    • pp.65-76
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    • 1989
  • The objective of this paper is to design the variable structure system(VSS) controller for the tracking control of excavator which is driven by electro-hydraulic servomechansim. It is generally agreed that the dynamic characteristics of the robot arm such as excavator are coupled, time varying, and highly nonlinear, and also hydraulic system contains nonlinear characteristics in itself, so performing exact position control and trajectory tracking control need remarkable consideration. To solve this porblem, this system was designed as a variable structure system. The salient feature of VSS is that the sliding mode occur on a switching surface. While in sliding mode, the system remains insensitive to parameter variations and disturbances. This control algorithm was applied to a hydraulic excavator by simulaltion and to a simulator by experiment. And its effectiveness was verified. And the results of VSS for the electro-hydraulic excavator was compared with that of the PID when load disturbances and system parameter variations exist.

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