• Title/Summary/Keyword: Changing algorithm

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Efficient Tracking of a Moving Object using Optimal Representative Blocks

  • Kim, Wan-Cheol;Hwang, Cheol-Ho;Lee, Jang-Myung
    • International Journal of Control, Automation, and Systems
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    • v.1 no.4
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    • pp.495-502
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    • 2003
  • This paper focuses on the implementation of an efficient tracking method of a moving object using optimal representative blocks by way of a pan-tilt camera. The key idea is derived from the fact that when the image size of a moving object is shrunk in an image frame according to the distance between the mobile robot camera and the object in motion, the tracking performance of a moving object can be improved by reducing the size of representative blocks according to the object image size. Motion estimations using Edge Detection (ED) and Block-Matching Algorithm (BMA) are regularly employed to track objects by vision sensors. However, these methods often neglect the real-time vision data since these schemes suffer from heavy computational load. In this paper, a representative block able to significantly reduce the amount of data to be computed, is defined and optimized by changing the size of representative blocks according to the size of the object in the image frame in order to improve tracking performance. The proposed algorithm is verified experimentally by using a two degree-of- freedom active camera mounted on a mobile robot.

A Simulation study of EWMA control using dynamic control parameter (동적 모수를 사용한 EWMA 제어의 시뮬레이션 연구)

  • Kang, Seok-Chan;Hwang, Ji-Bin;Kim, Sung-Shick;Kim, Ji-Hyun
    • Journal of the Korea Society for Simulation
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    • v.16 no.2
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    • pp.37-44
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    • 2007
  • EWMA is one of the most popular controller method used in Run-to-Run control system for semiconductor manufacturing. The value of the control parameter in EWMA has major effect on the result. Therefore, it is important to use control parameter value fitting for the process state. When the process is unstable, it is more efficient to change EWMA control parameter dynamically to compensate for the changing process state than using fixed control parameter. In this paper, we review previous studies using dynamic EWMA control parameter and propose a new algorithm complementing the weaknesses of the previous studies. The performance of the proposed algorithm is validated using simulation.

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Loss Minimization In Distribution Systems Using Reactive Tabu Search (Reactive Tabu Search 알고리즘을 이용한 배전계통의 손실 최소화)

  • 최상열;장경일;신명철
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.5
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    • pp.80-87
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    • 2003
  • Network reconfiguration in distribution systems is realized by changing the status of sectiona1izing switches, and is usually done for loss minimization or load balancing in the system This parer presents an approach for loss minization in distribution systems using reactive tabu search. Tabu search attempts to determine a better solution in the manner of a greatest-descent algorithm, but it can not give any guarantee for the convergence property. Reactive tabu search can give convergence property by using reaction and escape mechanism. Therefore, it can find global optimal solution regardless of initial system configuration. To demonstrate the validity of the proposed algorithm, numerical calculations are carried out the 32 bus system models.

A Study on the Sub Power Generator for Photovoltaic/Wind Hybrid System (태양광/풍력 복합발전의 보조 전력발생장치 개발에 대한 연구)

  • Park Se-Jun;Yoon Pil-Hyun;Lim Jung-Yeol;Lee Jeong-Il;Cha In-Su
    • Proceedings of the KIPE Conference
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    • 2003.11a
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    • pp.247-251
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    • 2003
  • The developments of the hybrid energy are necessary since the future alternative energies that have no pollution and no limitation are restricted. Currently power generation system of MW scale has been developed. However, even photovoltaic system cannot always generate stable output with ever-changing weather condition. In this paper, sub power generator for hybrid system(photovoltaic 500[W], wind power generation 400[W]) was suggested. Sub power Generator that uses elastic energy of spiral spring to photovoltaic system was also added for the present system. In an experiment, when output of photovoltaic system gets lower than 24[V] (charging voltage), power was continuously supplied to load through the inverter by charging energy obtained from generating rotary energy of spiral spring operates In DC generator. Also, control algorithm of sub power generator is used genetic algorithm(GA).

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Researches of the Real-time Medical Imaging Precessing Board using ASIC architecture (ASIC을 이용한 고속의료영상처리보드의 개발을 위한 기초연구)

  • Seo, J.H.;Park, H.M.;Ha, T.H.;Nam, S.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.299-300
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    • 1998
  • Recently the development of medical modality like as MRI, 3D US, DR etc is very active. Therefore it is more required not only the enhancement of quality in medical service but the improvement of medical system based on quantization, minimization, and optimization of high speed. Especially, as the changing into the digital modality system, it gets to start using ASIC(Application Specific Integrated Circuit) to realize one board system. It requires the implementation of hardware debugging and effective speedy algorithm with more speed and accuracy in order to support and replace existing device. If objected image could be linked to high speed process board with special interface and pre-processed using FPGA, it can be used in real time image processing and protocol of HIS(Hospital Information System). This study can support the basic circuit design of medical image board which is able to realize image processing basically using digitalized medical image, and to interface between existing device and image board containing image processing algorithm.

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Phase Synchronization Algorithm for High-speed Satellite Communications (고속 위성 통신용 위상 동기 방식)

  • ;Duc-Long
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.7A
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    • pp.836-843
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    • 2004
  • In per survivor processing (PSP) has a better performance than conventional phase offset estimators. But itsdefect is that it has a high complexity. In this paper, we propose the adaptive reduced state estimator (ARSE) algorithm not only to reduce the complexity, but also to have a good performance. The main principle of ARSE is changing the number of estimators dynamically during the decoding process according to the channel condition.

Approximate Multi-Objective Optimization of Robot Casting Considering Deflection and Weight (처짐과 무게를 고려한 주물 프레임의 다중목적 근사최적설계)

  • Choi, Ha-Young;Lee, Jongsoo;Park, Juno
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.21 no.6
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    • pp.954-960
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    • 2012
  • Nowadays, rapidly changing and unstable global economic environments request a lot of roles to engineers. In this situation, product should be designed to make more profit by cost down and to satisfy distinguished performance comparing to other competitive ones. In this research, the optimization design of the industrial robot casting will be done. The weight and deflection have to be reduced as objective functions and stress has to be constrained under some constant value. To reduce time cost, CCD (Central Composite Design) will be used to make experimental design. And RSM (Response Surface Methodology) will be taken to make regression model for objective functions and constraint function. Finally, optimization will be done with Genetic Algorithm. In this problem, the objective functions are multiple, so NSGA-II which is brilliant and efficient for such a problem will be used. For the solution quality check, the diversity between Pareto solutions will be also checked.

VEHICLE CRASH ANALYSIS FOR AIRBAG DEPLOYMENT DECISION

  • Hussain, A.;Hannan, M.A.;Mohamed, A.;Sanusi, H.;Ariffin, A.K.
    • International Journal of Automotive Technology
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    • v.7 no.2
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    • pp.179-185
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    • 2006
  • Airbag deployment has been responsible for huge death, incidental injuries and broken bones due to low crash severity and wrong deployment decision. This misfortune has led the authorities and the industries to pursue uniquely designed airbags incorporating crash-sensing technologies. This paper provides a thorough discussion underlying crash sensing algorithm approaches for the subject matter. Unfortunately, most algorithms used for crash sensing still have some problems. They either deploy at low severity or fail to trigger the airbag on time. In this work, the crash-sensing algorithm is studied by analyzing the data obtained from the variables such as (i) change of velocity, (ii) speed of the vehicle and (iii) acceleration. The change of velocity is used to detect crash while speed of the vehicle provides relevant information for deployment decision. This paper also demonstrates crash severity with respect to the changing speed of the vehicle. Crash sensing simulations were carried out using Simulink, Stateflow, SimMechanics and Virtual Reality toolboxes. These toolboxes are also used to validate the results obtained from the simulated experiments of crash sensing, airbag deployment decision and its crash severity detection of the proposed system.

High-frame-rate Video Denoising for Ultra-low Illumination

  • Tan, Xin;Liu, Yu;Zhang, Zheng;Zhang, Maojun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.4170-4188
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    • 2014
  • In this study, we present a denoising algorithm for high-frame-rate videos in an ultra-low illumination environment on the basis of Kalman filtering model and a new motion segmentation scheme. The Kalman filter removes temporal noise from signals by propagating error covariance statistics. Regarded as the process noise for imaging, motion is important in Kalman filtering. We propose a new motion estimation scheme that is suitable for serious noise. This scheme employs the small motion vector characteristic of high-frame-rate videos. Small changing patches are intentionally neglected because distinguishing details from large-scale noise is difficult and unimportant. Finally, a spatial bilateral filter is used to improve denoising capability in the motion area. Experiments are performed on videos with both synthetic and real noises. Results show that the proposed algorithm outperforms other state-of-the-art methods in both peak signal-to-noise ratio objective evaluation and visual quality.

Application of 4-D resistivity imaging technique to visualize the migration of injected materials in subsurface (지하주입 물질 거동 규명을 위한 4차원 전기비저항 영상화)

  • Kim, Jung-Ho;Yi, Myeong-Jong
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.12a
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    • pp.31-42
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    • 2007
  • Dc resistivity monitoring has been increasingly used in order to understand the changes of subsurface conditions in terms of conductivity. The commonly adopted interpretation approach which separately inverts time-lapse data may generate inversion artifacts due to measurement error. Eventually the contaminated error amplifies the artifacts when reconstructing the difference images to quantitatively estimate the change of ground condition. In order to alleviate the problems, we defined the subsurface structure as four dimensional (4-D) space-time model and developed 4-D inversion algorithm which can calculate the reasonable subsurface structure continuously changing in time even when the material properties change during data measurements. In this paper, we discussed two case histories of resistivity monitoring to study the ground condition change when the properties of the subsurface material were artificially altered by injecting conductive materials into the ground: (1) dye tracer experiment to study the applicability of electrical resistivity tomography to monitoring of water movement in soil profile and (2) the evaluation of cement grouting performed to reinforce the ground. Through these two case histories, we demonstrated that the 4-D resistivity imaging technique is very powerful to precisely delineate the change of ground condition. Particularly owing to the 4-D inversion algorithm, we were able to reconstruct the history of the change of subsurface material property.

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