• Title/Summary/Keyword: constancy

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Performance Evaluation of Color Constancy Methods for Low Illuminance (저조도를 위한 색 항등성 기법의 성능 평가)

  • Lee, Woo-Ram;Hwang, Dong-Guk;Jun, Byoung-Min
    • Proceedings of the KAIS Fall Conference
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    • 2011.12b
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    • pp.683-685
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    • 2011
  • 저조도 환경에서 획득된 영상은 대부분의 픽셀이 낮은 RGB 값을 가지기 때문에 물체가 가지는 색의 식별 및 물체 간의 구별이 어렵다는 문제점을 갖는다. 이러한 문제는 이론적으로 영상 내 존재하는 광원의 영향을 제거하는 것을 목적으로 하는 색 항등성 기법을 적용하여 해결이 가능하다. 저조도 영상에 적합한 색 항등성 기법을 찾기 위하여 본 논문에서는 Barnard 데이터 셋을 바탕으로 하는 저조도 합성 영상을 생성하고 이를 기반으로 다양한 색 항등성 기법을 평가한다. 저조도 합성 영상은 원하는 장면을 가지는 영상과 GTD를 생성할 수 있는 장점이 있기 때문에 실험 영상으로 사용된다. 성능 평가는 색 항등성 기법을 적용한 결과 영상과 GTD 영상을 비교하여 수행된다.

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Global Positioning of a Mobile Robot based on Color Omnidirectional Image Understanding (컬러 전방향 영상 이해에 기반한 이동 로봇의 위치 추정)

  • Kim, Tae-Gyun;Lee, Yeong-Jin;Jeong, Myeong-Jin
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.6
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    • pp.307-315
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    • 2000
  • For the autonomy of a mobile robot it is first needed to know its position and orientation. Various methods of estimating the position of a robot have been developed. However, it is still difficult to localize the robot without any initial position or orientation. In this paper we present the method how to make the colored map and how to calculate the position and direction of a robot using the angle data of an omnidirectional image. The wall of the map is rendered with the corresponding color images and the color histograms of images and the coordinates of feature points are stored in the map. Then a mobile robot gets the color omnidirectional image at arbitrary position and orientation, segments it and recognizes objects by multiple color indexing. Using the information of recognized objects robot can have enough feature points and localize itself.

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SPATIAL EXPLANATIONS OF SPEECH PERCEPTION: A STUDY OF FRICATIVES

  • Choo, Won;Mark Huckvale
    • Proceedings of the KSPS conference
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    • 1996.10a
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    • pp.399-403
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    • 1996
  • This paper addresses issues of perceptual constancy in speech perception through the use of a spatial metaphor for speech sound identity as opposed to a more conventional characterisation with multiple interacting acoustic cues. This spatial representation leads to a correlation between phonetic, acoustic and auditory analyses of speech sounds which can serve as the basis for a model of speech perception based on the general auditory characteristics of sounds. The correlations between the phonetic, perceptual and auditory spaces of the set of English voiceless fricatives /f $\theta$ s $\int$ h / are investigated. The results show that the perception of fricative segments may be explained in terms of 2-dimensional auditory space in which each segment occupies a region. The dimensions of the space were found to be the frequency of the main spectral peak and the 'peakiness' of spectra. These results support the view that perception of a segment is based on its occupancy of a multi-dimensional parameter space. In this way, final perceptual decisions on segments can be postponed until higher level constraints can also be met.

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Study on Insulation Design of Surge Voltages for Convex Winding type Ribbon Core Transformer (Convex형 권선배치방식을 취한 권철심변압기의 충격파절연설계에 관한 연구)

  • 황영문;조철제;김중한
    • 전기의세계
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    • v.22 no.3
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    • pp.13-24
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    • 1973
  • In this report, as a method to solve the problems on impulse insulation coordination in ribbon core transformer owing to it's BIL stepping up, new design to alter winding distribution of multiple-layer concentric winding to Convex type winding is proposed. The main focus of this method is to settle the weakness of axial direction insulation strength and as a result of theoretical analysis through experiment of model transformers, the following conclusions are obtained; (a) As the electric loadings in a design which increases by strengthenning axial direction insulation endurance in presently avarilable transformers owing to it's BIL stepping up can be restricted in Convex type winding, reasonable design will be suited to the transformer with higher BIL. (b) Convex type winding is a very improved insulation design in respect of insulation coordination because it has shield plate effect to even impulse oscillation. (c) There is a disadvantage to cause leakage flux to increase in Convex type winding, however, the constancy of electric loadings in a design in spite of BIL stepping up restricts the increase of leakage flux to some extent.

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PSA: A Photon Search Algorithm

  • Liu, Yongli;Li, Renjie
    • Journal of Information Processing Systems
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    • v.16 no.2
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    • pp.478-493
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    • 2020
  • We designed a new meta-heuristic algorithm named Photon Search Algorithm (PSA) in this paper, which is motivated by photon properties in the field of physics. The physical knowledge involved in this paper includes three main concepts: Principle of Constancy of Light Velocity, Uncertainty Principle and Pauli Exclusion Principle. Based on these physical knowledges, we developed mathematical formulations and models of the proposed algorithm. Moreover, in order to confirm the convergence capability of the algorithm proposed, we compared it with 7 unimodal benchmark functions and 23 multimodal benchmark functions. Experimental results indicate that PSA has better global convergence and higher searching efficiency. Although the performance of the algorithm in solving the optimal solution of certain functions is slightly inferior to that of the existing heuristic algorithm, it is better than the existing algorithm in solving most functions. On balance, PSA has relatively better convergence performance than the existing metaheuristic algorithms.

Color Enhancement of TV Picture Using Optical Sensor (광 센서를 이용한 TV 화상의 색 향상)

  • 이응주;김경만;박양우;정인갑;하영호
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1995.06a
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    • pp.69-74
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    • 1995
  • An object color can be seen differently under the various outer illuminants. However, human visual system has color constancy that the object color can be seen constantly under the different outer illuminants. When the viewer watches TV under specific outer illuminants, he perceives distorted color due to the emitting spectrum of outer illuminants as well as the radiation of CPT itself. Namely, when the outer illuminants such as fluorescent and incandescent lamps incident on CPT, brightness, saturation, hue, and contrast on color pictures are changed, he perceives distorted color from the original color. In this paper color enhancement algorithm based on light intensity and outer light decision function using RGB sensor was proposed. The implemented TV of proposed algorithm has higher visual quality at the view point of human visual system and more vivid than that of conventional color TV.

Statistical Methods in Non-Inferiority Trials - A Focus on US FDA Guidelines -

  • Kang, Seung-Ho;Wang, So-Young
    • The Korean Journal of Applied Statistics
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    • v.25 no.4
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    • pp.575-587
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    • 2012
  • The effect of a new treatment is proven through the comparison of a new treatment with placebo; however, the number of parent non-inferiority trials tends to grow proportionally to the number of active controls. In a non-inferiority trial a new treatment is approved by proof that the new treatment is not inferior to an active control; however, both additional assumptions and historical trials are needed to show (through the comparison of the new treatment with the active control in a non-inferiority trial) that the new treatment is more efficacious than a putative placebo. The two different methods of using the historical data: frequentist principle method and meta-analytic method. This paper discusses the statistical methods and different Type I error rates obtained through the different methods employed.

Face Detection using Simplified Horn Algorithm in Natural Image (Simplified Horn 기법을 이용한 자연 영상에서의 얼굴 영역 검출)

  • Lee, Woo-Ram;Hwang, Dong-Guk;Jun, Byoung-Min
    • Proceedings of the KAIS Fall Conference
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    • 2008.11a
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    • pp.320-322
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    • 2008
  • 본 논문에서는 조명의 변화에 강건한 얼굴 검출 알고리즘을 제안한다. 영상내의 조명 성분을 줄이기 위하여 컬러 일관성(color constancy) 알고리즘 중 Simplified Horn 기법을 적용한 후 색 정보를 이용하여 얼굴 후보영역을 결정한다. 이렇게 결정된 얼굴 후보영역 중 얼굴영역과 헤어영역의 여러 기하학적인 정보를 이용하여 실제 얼굴 영역을 판단한다. 제안한 알고리즘은 다양한 조명 성분을 갖는 여러 영상에서 테스트 되었으며 높은 검출률을 보였다.

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Optimization of Color and Gray Scale using Brightness Control in CRT Color Monitor

  • Kim, Hong-Suk;Park, Seung-Ok;Baek, Jung-Ki
    • 한국정보디스플레이학회:학술대회논문집
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    • 2000.01a
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    • pp.75-76
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    • 2000
  • Tone reproduction characteristics of color and gray have a great influence on the picture quality in visual display. In this study, we optimized tone reproduction characteristics of color and gray of CRT monitor by setting brightness to the optimum level, in which offsets for RGB channels can be assumed to zero. The optimum brightness level could be found by measuring a few tones of neutral for the combination of 2 levels of brightness and 2 levels of contrast. As the result, the relationship between normalized DAC count and normalized luminance of primary color or gray has been simply presented by gamma and result in good phosphor constancy.

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Social Role Development in Korean Preschool Children (학령전 아동의 사회역할 개념 발달)

  • Woo, Nam Hee
    • Korean Journal of Child Studies
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    • v.15 no.1
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    • pp.23-35
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    • 1994
  • This paper investigated children's learning process concerning age and gender, two of the most apparent social roles. The subjects of the study were 72 Korean preschool children between three to five years of age. The Study was designed to examine problems of developmental sequence and horizontal decalage in understanding of these social roles. Two five-step knowledge sequences of age growth and sex constancy were administered utilizing skill theory (Fischer, 1980). Each step in a sequence had different stories of age or sex role with increasing cognitive complexity, but the two sequences were equivalent in complexity. The children were tested under two different assessment conditions:high support condition of elicited imitation and low support condition of free play and the best story. The findings show that, the understanding of age and sex roles develops through the predicted five-step sequences. The understanding of age role seems to develop earlier than that of sex role although the developmental patterns of the two roles are similar. Variations in the children's performances under different conditions were dramatic, especially for the older children.

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