• Title/Summary/Keyword: variable feature

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Analysis of a Modified Stochastic Gradient-Based Filter with Variable Scaling Parameter (가변 축척 매개변수를 가진 변형 확률적 경사도 기반 필터의 해석)

  • Kim, Hae-Jung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.12C
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    • pp.1280-1287
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    • 2006
  • We propose a modified stochastic gradient-based (MSGB) filter showing that the filter is the solution to an optimization problem. This paper analyzes the properties of the MSGB filter that corresponds to the nonlinear adaptive filter with additional update terms, parameterized by the variable scaling factor. The variably parameterized MSGB filter plays a role iii connecting the fixed parameterized MSGB filter and the null parameterized MSGB filter through variably scaling parameter. The stability regions and misadjustments are shown. A system identification is utilized to perform the computer simulation and demonstrate the improved performance feature of the MSGB filter.

A New Stereo Matching Algorithm based on Variable Windows using Frequency Information in DWT Domain (DWT 영역에서의 주파수 정보를 활용한 가변 윈도우 기반의 스테레오 정합 알고리즘)

  • Seo, Young-Ho;Koo, Ja-Myung;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1437-1446
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    • 2012
  • In this paper we propose a new stereo matching algorithm which is suitable for application to obtain depth information with high-speed in stereoscopic camera environment. For satisfying these condition we propose a new adaptive stereo matching technique using frequency information in discrete wavelet (DWT) domain and variable matching window. The size of the matching window is selected by analysis of the local property of the image in spatial domain and the feature and scaling factor of the matching window is selected by the frequency property in the frequency domain. For using frequency information we use local DWT and global DWT. We identified that the proposed technique has better peak noise to signal ratio (PSNR) than the fixed matching techniques with similar complexity.

Mechanics of a variable damping self-centering brace: Seismic performance and failure modes

  • Xie, Xing-Si;Xu, Long-He;Li, Zhong-Xian
    • Steel and Composite Structures
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    • v.31 no.2
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    • pp.149-158
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    • 2019
  • The force-deformation behavior, strain distribution and failure modes of a variable damping self-centering brace (VD-SCB) are theoretically analyzed, experimentally studied, and numerically simulated to guide its design. The working principle of the brace is explained by describing the working stages and the key feature points of the hysteretic curve. A large-scale brace specimen was tested under different sinusoidal excitations to analyze the recentering capability and energy dissipation. Results demonstrate that the VD-SCB exhibits a full quasi-flag-shaped hysteretic response, high ultimate bearing capacity, low activation force and residual deformation, and excellent recentering and energy dissipation capabilities. Calculation equations of the strain distribution in different parts of the brace are proposed and are compared with the experimental data and simulated results. The developments of two failure modes are compared. Under normal circumstances, the brace fails due to the yielding of the spring blocking plates, which are easily replaced to restore the normal operating conditions of the brace. A brief description of the design procedure of the brace is proposed for application.

Performance Comparison of Neural Network Algorithm for Shape Recognition of Welding Flaws (초음파 검사 기반의 용접결함 분류성능 개선에 관한 연구)

  • 김재열;윤성운;김창현;송경석;양동조
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.04a
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    • pp.287-292
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    • 2004
  • In this study, we made a comparative study of backpropagation neural network and probabilistic neural network and bayesian classifier and perceptron as shape recognition algorithm of welding flaws. For this purpose, variables are applied the same to four algorithms. Here, feature variable is composed of time domain signal itself and frequency domain signal itself, Through this process, we confirmed advantages/disadvantages of four algorithms and identified application methods of few algorithms.

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Growing Pulmonary Aspergilloma for 10 Years - One Case Report - (10년 동안 성장한 거대 폐국균종 치험 1례)

  • 심성보
    • Journal of Chest Surgery
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    • v.24 no.8
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    • pp.814-818
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    • 1991
  • Infection with the ubiquitous fungus Aspergillus is uncommon. This organism has a low pathogenicity for man. In most patients, pulmonary Aspergilloma is the most common form of disease, and Aspergillus fumigatus is the common species. The natural history of the pulmonary aspergilloma is variable. This report reviews the feature of growing pulmonary aspergilloma for 10 years[from diameter 3cm to diameter 9cm]. This 44-year-old male patient suffered from recurrent hemoptysis for 10 years. This patient was taken removal of aspergilloma and cavernoplasty of left upper lobe. Post-operation course was uneventful.

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Performance Comparison of Neural Network Algorithm for Shape Recognition of Welding Flaws (용접결함의 형상인식을 위한 신경회로망 알고리즘의 성능 비교)

  • 김재열;심재기;이동기;김창현;송경석;양동조
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2003.10a
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    • pp.271-276
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    • 2003
  • In this study, we compared backpropagation neural network(BPNN) with probabilistic neural network(PNN) as shape recognition algorithm of welding flaws. For this purpose, variables are applied the same to two algorithm. Here, feature variable is composed of time domain signal itself and frequency domain signal itself, Through this process, we comfirmed advantages/disadvantages of two algorithms and identified application methods of two algorithms.

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Performance Comparison of Welding Flaws Classification using Ultrasonic Nondestructive Inspection Technique (초음파 비파괴 검사기법에 의한 용접결함 분류성능 비교)

  • 김재열;유신;김창현;송경석;양동조;김유홍
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
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    • 2004.10a
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    • pp.280-285
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    • 2004
  • In this study, we made a comparative study of backpropagation neural network and probabilistic neural network and bayesian classifier and perceptron as shape recognition algorithm of welding flaws. For this purpose, variables are applied the same to four algorithms. Here, feature variable is composed of time domain signal itself and frequency domain signal itself. Through this process, we comfirmed advantages/disadvantages of four algorithms and identified application methods of four algorithms.

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High accuracy measurement of the position and orientation of SMD VR by Computer Vision (비젼을 이용한 SMD 부품의 위치 및 자세 계측)

  • 김병엽;송재용;한창수;박종현;이영민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.04b
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    • pp.371-376
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    • 1995
  • Computer vision is applicated to measure the position and orientation of the SMD on 8mm Camcoder PCB and advanced image processing algorithms for high accuracy and real time processing are proposed. Illumination conditions are optimized for the best image formation and a set of LEDs is used as economic illuminator, which is regarded as a summation of many point sources. Conctete optical system is constructed and the performance of the proposed algorithm is verified by several experiments.

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A study on the new gamut mapping method for digital soft color proofing (디지털 소프트 칼라 교정인쇄를 위한 새로운 색역 사상방법에 관한 연구)

  • 송경철;강상훈
    • Proceedings of the Korean Printing Society Conference
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    • 2002.05a
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    • pp.10-18
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    • 2002
  • On the process of cross-media color reproduction, a key feature is the use of gamut mapping techniques to adjust the different color gamuts between displays and printers. Even though a number of GMAs have been published, but there are no method satisfactory enough for more exect color reproduction. In this paper, the gamut mapping methods of nearest point clipping(NPC), centroid clipping (SLIN), straight clipping and cusp clipping(CUSP) were tested and analyzed with color difference, and a new gamut mapping algorithm based on variable anchor point method was proposed.

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Two-Degree-of-Freedom PID controller with Neural network for position control (위치제어를 위한 신경망 2 자유도 PID 제어기)

  • 이정민;하홍곤
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2000.12a
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    • pp.193-196
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    • 2000
  • ln this paper, we consider to apply of 2-DOF (Degree of Freedom) PID controller at D.C servo motor system. Many control system use I-PD, PIB control system. but the position control system have difficulty in controling variable load and changing parameter We propose neural network 2-DOF PID control system having feature for removal disturbrances and tracking function in the target value point.

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