• 제목/요약/키워드: Visual sensitivity

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A New Unified Design Environment for Optimization of Electric Machines Based on Continuum Sensitivity and B-Spline Parametrization

  • Kim, Min-Ho;Lee, Hyang-Beom;Kim, Hyeong-Seok;Byun, Jin-Kyu
    • Journal of Electrical Engineering and Technology
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    • v.6 no.4
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    • pp.513-518
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    • 2011
  • In this paper, a unified design environment is developed for the optimization of electric machines based on continuum sensitivity. For electromagnetic (EM) system analysis, COMSOL scripting environment is used. Optimization module is developed by MATLAB programming, which can be combined with COMSOL script commands. The modules are combined into one MATLAB project, and iteration process necessary for the optimization of EM system can be performed efficiently. During the design process, visual feedback of the current design status is given to the designer. In addition, the B-Spline parametrization of the nodal points is implemented to obtain smooth boundary of the device. The developed software is applied to the problem of finding uniform flux density distribution at the air gap of an electromagnet to verify its feasibility and effectiveness.

A Property Analysis of Parameters for Effective Watermarking based on Human Visual System (HVS 기반 효과적인 워터마킹을 위한 파라미터 성능분석)

  • Park Ki-Hong;Yoon Byung-Min;Kim YoonHo
    • Journal of Digital Contents Society
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    • v.6 no.2
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    • pp.119-123
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    • 2005
  • We proposed a method of effective watermarking based m HVS. To speak generally, HVS parameters are contrast sensitivity, texture degree, entropy sensitivity and standard of deviation, etc. The aim of this paper is evaluated by the experiments of imperceptibility and correctness of watermark. According to some experimental results, contrast sensitivity function is superior in smooth image. On the other hand, standard of deviation provides good results in rough images. Consequently, how to select the parameters considering image attribute is key problem in effective watermarking.

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Sensitivity analysis of mechanical behaviors for bridge damage assessment

  • Miyamoto, Ayaho;Isoda, Satoshi
    • Structural Engineering and Mechanics
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    • v.41 no.4
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    • pp.539-558
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    • 2012
  • The diagnosis of bridge serviceability is carried out by a combination of in-situ visual inspection, static and dynamic loading tests and analyses. Structural health monitoring (SHM) using information technology and sensors is increasingly being used for providing a better estimate of structural performance characteristics rather than above traditional methods. Because the mechanical behavior of bridges with various kinds of damage can not be made clear, it is very difficult to estimate both the damage mode and degree of damage of existing bridges. In this paper, the sensitivity of both static and dynamic behaviors of bridges are studied as a measure of damage assessment through experiments on model bridges induced with some specified artificial damages. And, a method of damage assessment of bridges based on those behaviors is discussed in detail. Finally, based on the results, a possible application for structural health monitoring systems for existing bridges is also discussed.

Characterizing Information Processing in Visual Search According to Probability of Target Prevalence (표적 출현확률에 따른 시각탐색 정보처리 특성)

  • Park, Hyung-Bum;Son, Han-Gyeol;Hyun, Joo-Seok
    • Korean Journal of Cognitive Science
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    • v.26 no.3
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    • pp.357-375
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    • 2015
  • In our daily life, the probability of target prevalence in visual search varies from very low to high. However, most laboratory studies of visual search used a fixed probability of target prevalence at 50%. The present study examined the properties of information processing during visual search where the probability of target prevalence was manipulated to vary from low (20%), medium (50%), to high (80%). The search items were made of simple shape stimuli, and search accuracy, signal detection measures, and reaction times (RTs) were analyzed for characterizing the effect of target prevalence on the information processing strategies for visual search. The analyses showed that the rates of misses increased whereas those of false alarms decreased in the search condition of low target prevalence, whereas the pattern was reversed in the high prevalence condition. Signal detection measures revealed that the target prevalence shifted response criterion (c) without affecting sensitivity (d'). In addition, RTs for correct rejection responses in the target-absent trials became delayed as the prevalence increased, whereas those for hits in the target-present trials were relatively constant regardless of the prevalence. The RT delay in the target-absent trials indicates that increased target prevalence made the 'quitting threshold' for search termination more conservative. These results support an account that the target prevalence effect in visual search arises from a shift of decision criteria and the subsequent changes in search information processing, while rejecting the account of a speed-accuracy tradeoff.

Subjective appraisal of the appearance on monochromatic light differenced by the eyeball's pigment

  • Muraoka, Tetsuya;Ikeda, Hiroaki
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10b
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    • pp.1009-1013
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    • 1990
  • In the Orient, most references are made on the visual perception of the eye having the blue iris, even in the case where the reference should be made on the perception by the eye having the dark iris. In order to clarify the difference in the visual perceptions of a monochromatic light, an objective boundary wavelength between hues incident on the dark eyes was obtained and the correlation between the valuesalready reported as having been obtained with the blue eyes was examined. A significant difference was found in the subjective boundary wavelengths of hues depending on the difference in the visual sensitivity distribution on the dark and blue eyes.

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Defect Detection Method using Human Visual System and MMTF (MMTF와 인간지각 특성을 이용한 결함성분 추출기법)

  • Huh, Kyung-Moo;Joo, Young-Bok
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.12
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    • pp.1094-1098
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    • 2013
  • AVI (Automatic Vision Inspection) systems automatically detect defect features and measure their sizes via camera vision. Defect detection is not an easy process because of noises from various sources and optical distortion. In this paper the acquired images from a TFT panel are enhanced with the adoption of an HVS (Human Visual System). A human visual system is more sensitive on the defect area than the illumination components because it has greater sensitivity to variations of intensity. In this paper we modified an MTF (Modulation Transfer Function) in the Wavelet domain and utilized the characteristics of an HVS. The proposed algorithm flattens the inner illumination components while preserving the defect information intact.

Thermo-Visual Evaluations of Acute Abdomen Pain in Children

  • Aleck Ovechkin;Kyeong-Seop Kim;Jeong-Whan Lee;Sang-Min Lee
    • KIEE International Transaction on Systems and Control
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    • v.2D no.2
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    • pp.59-64
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    • 2002
  • About two thirds of patients admitted to hospitals world-wide suffer from acute abdomen pains of varying degrees of severity. Acute abdomen pain due to appendicitis or pancreatitis usually requires urgent surgical treatment, whereas pain due to heart ischemia or enteroviral infection requires only drug treatment. In general, making an immediate decision about whether or not acute abdomen pain requires urgent surgery is very difficult. This decision becomes even more difficult when the patient is a young child who can't properly describe the abdominal pain. In this case, thermo-visual inspection can alternatively be used to decide whether urgent surgical treatment is necessary to cure the abdominal pain.

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Human Visual System Adaptive Image Enhancement (Human Visual System에 적응적인 영상 화질 향상 기법)

  • Bang, Seang-Bae;kim, won-ha
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2016.11a
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    • pp.114-116
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    • 2016
  • 본 논문은 human visual system(HVS)에 따른 주파수 민감도와 공간에서 다양한 특성들을 구현하기 위한 신호처리 방법을 개발하였다. 인간의 눈은 주파수 성분에 따라 민감도가 다르며 초점에서 멀수록 인지 가능한 해상도가 떨어진다. 주파수 민감도를 구현하기 위해서 본 논문은 영상 신호의 에너지 스펙트럼 모양이 contrast sensitivity function(CSF)의 모양이 되도록하여 영상 신호의 에너지를 증가시켰으며 신호 방향에 적응적인 multiband energy scaling 방법을 개발하였다. 기존의 시스템에서 능률만을 향상시키는 기존의 분석 모델과 비교하면 개발한 방법은 HVS에 좀 더 적절하고 선호되게 영상 신호를 처리 할 수 있다.

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[Retracted]The effect of Massage and Paraffin on Cold Hypersensitivity Patient ([논문표절]수족냉증에 적용한 마사지와 파라핀의 효과)

  • Roh, Hyo-lyun
    • Proceedings of the Korea Contents Association Conference
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    • 2017.05a
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    • pp.101-102
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    • 2017
  • This study of purpose was to evaluate the changes in hands and feet temperature by applying massage and paraffin bath.. The subject of this study was 30 university healthy students. Subjects were divided into paraffin bath group and massages group. The digital infrared thermographic imaging was used for thermographic analysis. The visual analog scale was used for subjective information about the degree of cold sensitivity and cold stress test was used for analyzing the temperature recovery rate. After the interventions showed that temperature difference of the right hand and temperature difference of the left hand are less in the paraffin group than the massage group. When applied paraffin bath and massage to the cold hypersensitivity patient the massage group showed difference in the visual analog scale and the paraffin group showed difference in the temperature of the right hand, left hand, left foot and in the visual analog scale. Paraffin bath treatment seems to be useful to patients with cold hypersensitivity on hands and feet.

Effects of Visual Perception Skills on Driving Performance of Patients With Stroke (뇌졸중 환자의 시지각 능력이 운전수행에 미치는 영향)

  • Kwak, Ho-Soung
    • Therapeutic Science for Rehabilitation
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    • v.9 no.1
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    • pp.45-55
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    • 2020
  • Objective : The purpose of this study was to investigate the effects of visual perception on driving performance and the importance of visual training for improving driving performance in patients with stroke. Methods : The evaluations, using MVPT(Motor-free Visual Perception Test), TMT A&B(Trail Making Test A & B), UFOV(Useful Field Of View test), and a driving simulator, were carried out with patients in department of physical medicine and rehabilitation in a rehabilitation hospital from October 2014 to November 2014. Results : Driving performance was related to the ability of various visual perceptions of patients with stroke, and the highest correlation was found in the UFOV subtest 2, TMT B, and MVPT. The results of discriminant analysis indicated a sensitivity of 100.0%, specificity of 80.0%, and predicted the results of the driving simulator with 89.5% accuracy. Conclusion : This study found that visual-perception skills influence driving performance and suggested the importance of visual-perception skill training for driving.