• Title/Summary/Keyword: 수렴영역

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Tracking of eyes based on the iterated spatial moment using weighted gray level (명암 가중치를 이용한 반복 수렴 공간 모멘트기반 눈동자의 시선 추적)

  • Choi, Woo-Sung;Lee, Kyu-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.14 no.5
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    • pp.1240-1250
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    • 2010
  • In this paper, an eye tracking method is presented by using on iterated spatial moment adapting weighted gray level that can accurately detect and track user's eyes under the complicated background. The region of face is detected by using Haar-like feature before extracting region of eyes to minimize an region of interest from the input picture of CCD camera. And the region of eyes is detected by using eigeneye based on the eigenface of Principal component analysis. Also, feature points of eyes are detected from darkest part in the region of eyes. The tracking of eyes is achieved correctly by using iterated spatial moment adapting weighted gray level.

공액근사개념 및 변위장 반복계산에 의한 국부응력장 개선 연구

  • 송기남
    • Proceedings of the Korean Nuclear Society Conference
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    • 1997.05b
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    • pp.495-502
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    • 1997
  • 변위형 유한요소해에 기초하고 공액근사개념 및 Loubignac의 변위장 개선방법을 국부영역에 적용하여 국부영역에서의 응력장의 정확도를 향상시킬 수 있는 방법을 제안하였다. 제안된 방법에서 계산된 국부영역의 응력장은 전체영역에 대한 응력장 개선 결과에 근접하며 유한요소 평형방정식을 잘 만족하친 있을 뿐만 아니라 수회 이내의 반복계산내에 수렴하고 있어서 계산시간이 크게 줄어들 수 있어서 국부영역에 대한 상세응력해석에 적절하게 이용될 수 있다.

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Development of Elements of Horticultural Therapy Evaluation Indices (HTEI) through Delphi Method (전문가 델파이 조사를 통한 원예치료 평가지표 구성요소 개발)

  • Im, Eun-Ae;Son, Ki-Cheol;Kam, Jeong-Ki
    • Horticultural Science & Technology
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    • v.30 no.3
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    • pp.308-324
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    • 2012
  • The aim of this study is to develop and construct the elements of a new evaluation tool to assess the effectiveness of a horticultural therapy. Delphi method was applied to classify the realms of evaluation and specify their components and constituting items. Delphi process was performed through three rounds and 24 professionals attended all the rounds as panel members. Some of the items were revised or removed according to the results of such tests as content validity ratio, agreement rate, convergency and stability of each item. On the contrary, a few new items were added by accepting the opinions of the professional panels. Previous to the Delphi, the realms of evaluation were classified into physical, cognitional, psycho-emotional and social ones on the basis of literature review, professionals' consultation and in-depth interview with practitioners. At the first round, 112 items constituting four realms were reviewed. The numbers of items to be reviewed were reduced to 107 at the second round and to 102 at the third round. As a result, 98 items in 4 realms were decided as proper evaluation points of horticultural therapy. The compositions of the four respective realms are as follows: 5 components and 27 items in physical realm; 4 components and 25 items in cognitional realm; 2 components and 24 items in psycho-emotional realm; and 4 components and 22 items in social realm. These realms, components and specific items derived from this study constitute indices to evaluate the effectiveness of horticultural therapy. In addition, they might be utilized as good guidelines for planning horticultural therapy programs.

Temperature Preconditioning for Improving Convergence Characteristics in Calculating Low Mach Number Flows, II: Navier-Stokes Equations (저속 유동 계산의 수렴성 개선을 위한 온도예조건화 II: 나비어스톡스 방정식)

  • Lee, Sang-Hyeon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.35 no.12
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    • pp.1075-1081
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    • 2007
  • The temperature preconditioning is applied to the Navier-Stokes equations. Also, a new concept of diffusion Mach numbers is introduced to modify the reference Mach number for the Navier-Stokes equations. Flows over a circular cylinder were calculated at different Reynolds numbers. It is shown that the temperature preconditioning improves the convergence characteristics of Navier-Stokes equations. Also, it is shown that the modified reference Mach number alleviates the convergence problems at locally low speed regions.

Hierarchic Shell Model Based on p-Convergence (p-수렴방식에 기초한 계층요소 쉘 모델)

  • 우광성
    • Computational Structural Engineering
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    • v.3 no.1
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    • pp.59-70
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    • 1990
  • The p-version of the finite element method is a new approach to finite element analysis in which the partition of the domain is held fixed while the degree p of approximating piecewise polynomials is increased. In this paper, the focus is on computer implementation of a new hierarchic p-convergence shell model based on blend mapping functions. Its rigid-body modes, round-off error, and convergence characteristics are investigated.

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An Implementation of Acoustic Echo Canceller Using Adaptive Filtering in Modulated Lapped Transform Domain (Modulated Lapped Transform 영역에서 적응 필터링을 이용한 음향 반향 제거기의 구현)

  • 백수진;박규식
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.6
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    • pp.425-433
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    • 2003
  • Acoustic Echo Canceller (AEC) is a signal processing system for removing unwanted echo signals in teleconference and hands-free communication. Least mean square (LMS) algorithm is one of the adaptive echo cancellation algorithms and it has been most attractive because of its simplicity and robustness. However, the convergence properties of the LMS algorithm degrade with highly correlated input signals such as speech. For this reason, transform-domain adaptive filtering algorithm was introduced to decorrelate the colored input samples by using the orthogonal transform matrix such as DCT, DFT and then LMS adaptive filtering process is applied. In this paper, we propose a MLT domain adaptive echo canceller base on the MLT (Modulated lapped Transform) orthogonal transform matrix. The proposed algorithm achieves high decorrelation efficiency and fast convergence speed via modulated lapped transform of size 2NXN instead of NXN unitary transform such as DCT, DFT, Hadamad and it is applied to the acoustical echo cancellation system. Form the computer simulation with both synthesis and real speech, the proposed MLT domain adaptive echo canceller shows approximately twice faster convergence speed and 20∼30 ㏈ ERLE improvements over the DCT frequency domain acoustic echo cancellation system.

An Improved Fractal Color Image Decoding Based on Data Dependence and Vector Distortion Measure (데이터 의존성과 벡터왜곡척도를 이용한 개선된 프랙탈 칼라영상 복호화)

  • 서호찬;정태일;류권열;권기룡;문광석
    • Journal of Korea Multimedia Society
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    • v.2 no.3
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    • pp.289-296
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    • 1999
  • In this paper, an improved fractal color image decoding method using the data dependence parts and the vector distortion measure is proposed. The vector distortion measure exploits the correlation between different color components. The pixel in RGB color space can be considered as a 30dimensional vector with elements of RGB components. The root mean square error(rms) in RGB color for similarity measure of two blocks R and R' was used. We assume that various parameter necessary in image decoding are stored in the transform table. If the parameter is referenced in decoding image, then decoding is performed by the recursive decoding method. If the parameter is not referenced in decoding image, then the parameters recognize as the data dependence parts and store its in the memory. Non-referenced parts can be decoded only one time, because its domain informations exist in the decoded parts by the recursive decoding method. Non-referenced parts are defined the data dependence parts. Image decoding method using data dependence classifies referenced parts and non-referenced parts using information of transform table. And the proposed method can be decoded only one time for R region decoding speed than Zhang & Po's method, since it is decreased the computational numbers by execution iterated contractive transformations for the referenced range only.

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A fast decoding algorithm using data dependence in fractal image (프래탈 영상에서 데이타 의존성을 이용한 고속 복호화 알고리즘)

  • 류권열;정태일;강경원;권기룡;문광석
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.10
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    • pp.2091-2101
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    • 1997
  • Conventional method for fractal image decoding requires high-degree computational complexity in decoding propocess, because of iterated contractive transformations applied to whole range blocks. In this paper, we propose a fast decoding algorithm of fractal image using data depence in order to reduce computational complexity for iterated contractive transformations. Range of reconstruction image is divided into a region referenced with domain, called referenced range, and a region without reference to domain, called unreferenced range. The referenced range is converged with iterated contractive transformations, and the unreferenced range can be decoded by convergence of the referenced range. Thus the unreferenced range is called data dependence region. We show that the data dependence region can be deconded by one transformation when the referenced range is converged. Consequently, the proposed method reduces computational complexity in decoding process by executing iterated contractive transformations for the referenced range only.

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Design of Dual Fuzzy Logic Controller using $e-{\Delta}e$ Phase Plane for Hydraulic Servo Motor (유압 서보 모터를 위한 $e-{\Delta}e$ 위상평면을 이용한 이중 퍼지 로직 제어기 설계)

  • Shin, Wee-Jae;Moon, Jeong-Hoon
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.3
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    • pp.222-226
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    • 2007
  • In this paper we composed the dual fuzzy rules using each region of specific points and $e-{\Delta}e$ phase plane In order to make dual fuzzy rule base. We composed the fuzzy control rules which can decrease rise time, delay time, maximum overshoot than basic fuzzy control rules. proposed method is alternately use at specific points of $e-{\Delta}e$ phase plane with two fuzzy control rules that is one control rule occruing the steady state error in transient region and another fuzzy control rule use to decrease the steady state error and rapidly converge at the convergence region. Also, two fuzzy control rules in the $e-{\Delta}e$ phase plane decide the change time according to response characteristics of plants. In order to confirm thef proposed algorithm. As the results of experiments through the hydraulic servo motor control system with a DSP processor, We verified that proposed dual fuzzy control rules get the good response compare with the basic fuzzy control rule.

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Adaptive blind equalization algorithm with dual-mode (이중 모드를 가지는 적응 블라인드 등화 알고리즘)

  • 정영화;진용옥
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.9
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    • pp.2005-2013
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    • 1997
  • The MCMA adaptive blind equalization algorithm has a excellent phase correction capabilities in addition to channel amplitude equalization, but has an inevitable error by mismatching between the original constellation points in arriving at the perfect equalization since unique new type constellation points are used as desired response instead of original constellation points and follows the slow convergence speed of CMA. In this paper, We propose an adaptive blind equalization algorithm with dual-mode, which has decision regions. Inside the decision regions, it operates as considering the moudlus of original data symbol point and outside the decision region, it operates as considerin gthe modulus of new constellation points. The proposed algorithm has a lower error in the steady state and rapid convergence speed toward steady state using the original data symbol points instead of new constellation points in the decision regions. From computer simulation, we confirm that the propposed algorithm has the performance superiority in residual ISI, convergence speed compared with the cnventional adaptive blind equalization algorithms, CMA, MCMA, Stop-and-Go algorithm.

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