• Title/Summary/Keyword: Visual Distance

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Combustible Gas and Visible Distance by Sprinkler Head for Safety of Gymnasium Workers

  • Ahn, Jae-Cheon;Kong, Ha-Sung
    • International journal of advanced smart convergence
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    • v.10 no.3
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    • pp.232-244
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    • 2021
  • This study analyzed the changes in carbon monoxide, carbon dioxide, oxygen and visual distance by presence of sprinkler heads and their types in the event of a fire in an indoor gymnasium. Based on carbon monoxide and visual distance that affects human bodies enormously, first, if there is no sprinkler head, carbon monoxide will reach 0.4% within five seconds and visual distance rapidly shrank within five seconds. Seconds, in the event of standard sprinkler heads, carbon monoxide gradually increased from 30 seconds onwards and visual distance rapidly shrank after five seconds. Second, Third, if there are special sprinkler heads, carbon monoxide fluctuated after opening the head and visual distance became 5m or below from 15 seconds. Finally, in the event of early response sprinkler heads, carbon monoxide fluctuated up and down at 3 seconds due to falling water drops. Visual distance shrank up to 5m or below at 6 seconds. In the future, time for operation of each sprinkler head shall be analyzed.

Development of a Robot's Visual System for Measuring Distance and Width of Object Algorism (로봇의 시각시스템을 위한 물체의 거리 및 크기측정 알고리즘 개발)

  • Kim, Hoi-In;Kim, Gab-Soon
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.2
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    • pp.88-92
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    • 2011
  • This paper looks at the development of the visual system of robots, and the development of image processing algorism to measure the size of an object and the distance from robot to an object for the visual system. Robots usually get the visual systems with a camera for measuring the size of an object and the distance to an object. The visual systems are accurately impossible the size and distance in case of that the locations of the systems is changed and the objects are not on the ground. Thus, in this paper, we developed robot's visual system to measure the size of an object and the distance to an object using two cameras and two-degree robot mechanism. And, we developed the image processing algorism to measure the size of an object and the distance from robot to an object for the visual system, and finally, carried out the characteristics test of the developed visual system. As a result, it is thought that the developed system could accurately measure the size of an object and the distance to an object.

Eye Movement-based Visual Discomfort Analysis from Watching Stereoscopic 3D Contents Regarding Brightness and Viewing Distance (눈 움직임을 이용한 밝기와 시청거리에 따른 3D 콘텐츠 피로도 분석)

  • Kim, Yong-Woo;Kang, Hang-Bong
    • Journal of Korea Multimedia Society
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    • v.19 no.9
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    • pp.1723-1737
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    • 2016
  • When watching 3D contents, people often experience various visual discomforts like tiredness, dryness, headaches, and dizziness. Previous researches on visual discomfort analyzed and concluded vergence-accommodation conflict, viewing distance, and brightness changes to be the causes of visual discomfort. Yet it is necessary to systematically analyze the visual discomfort due to the changes in object, background brightness and viewing distance. In this paper, we produce four videos that have four different background brightness and two different viewing distances to solve analyze the visual discomfort from watching 3D contents. We measure and analyze eye-blink and saccadic movement, saccadic latency, Nearest Point of Convergence (NPC), and participant survey for amore accurate result compared to previous researches. Our results show that the eye-blink rate and saccadic latency increase when the background is bright and viewing distance is close while the saccadic movement decreases in the same environment. However, NPC only changes when the background brightness changes. We confirm that the bright background and near viewing distance create greater visual discomfort and decrease depth perception abilities.

Development of a Calculating Program for the Prism Power Influencing to Binocular Vision according to Shift of Binocular Visual Points in the Distance Vision Spectacles (원용안경의 양안 주시점 이동에 따른 양안시에 미치는 프리즘 굴절력 산출 프로그램 개발)

  • Lee, Dong-Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.15 no.3
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    • pp.257-262
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    • 2010
  • Purpose: Developing a calculating program for the prism power which influenced the binocular vision according to shifts of binocular visual points in the distance vision spectacles. Methods: By using the Delphi 6.0 programming language, we developed a calculating program of the relative binocular prism power according to the movements of binocular visual points in the distance vision spectacles, which was calculated by dragging the mouse along the traces of binocular visual points on the computer window. Results: We developed a calculating program for the relative binocular prism power according to the movements of binocular visual points in the distance vision spectacles. The user of the program could confirm the trace of visual points by allowing them to display the trace of binocular visual points on the computer screen with a mouse button. An application on confirming the variation of prism power by graphs in the program also allowed the user to use the program more conveniently. Conclusions: By using the developed program, the user could easily calculate the relative binocular prism power according to shifts of binocular visual points in the distance vision spectacles. We also found that the developed program helped the user to receive a lot of assistance in analyzing the asthenopia.

Audio-visual Spatial Coherence Judgments in the Peripheral Visual Fields

  • Lee, Chai-Bong;Kang, Dae-Gee
    • Journal of the Institute of Convergence Signal Processing
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    • v.16 no.2
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    • pp.35-39
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    • 2015
  • Auditory and visual stimuli presented in the peripheral visual field were perceived as spatially coincident when the auditory stimulus was presented five to seven degrees outwards from the direction of the visual stimulus. Furthermore, judgments of the perceived distance between auditory and visual stimuli presented in the periphery did not increase when an auditory stimulus was presented in the peripheral side of the visual stimulus. As to the origin of this phenomenon, there would seem to be two possibilities. One is that the participants could not perceptually distinguish the distance on the peripheral side because of the limitation of accuracy perception. The other is that the participants could distinguish the distances, but could not evaluate them because of the insufficient experimental setup of auditory stimuli. In order to confirm which of these two alternative explanations is valid, we conducted an experiment similar to that of our previous study using a sufficient number of loudspeakers for the presentation of auditory stimuli. Results revealed that judgments of perceived distance increased on the peripheral side. This indicates that we can perceive discrimination between audio and visual stimuli on the peripheral side.

카메라 디포커싱을 이용한 로보트의 시각 서보

  • 신진우;고국현;조형석
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1994.10a
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    • pp.559-564
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    • 1994
  • Recently, a visual servoing for an eye-in-hand robot has become an interesting problem. A distance between a camera and a task object is very useful information for visual servoing. In the previous works for visual servoing, the distance can be obtained from the difference between a reference and a measured feature value of the object such as area on image plane. However, since this feature depends on the object, the reference feature value must be changed when other task object is taken. To overcome this difficulty, this paper presents a novel method for visual servoing. In the proposed method, a blur is used to obtain the distance. The blur, one of the most important features, depends on the focal length of camera. Since it is not affected by the change of object, the reference feature value is not changed although other task object is taken. In this paper, we show a relationship between the distance and the blur, and define the feature jacobian matrix based on camera defocusing to operate the robot. A series of experiments is performed to verify the proposed method.

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A Camera Pose Estimation Method for Rectangle Feature based Visual SLAM (사각형 특징 기반 Visual SLAM을 위한 자세 추정 방법)

  • Lee, Jae-Min;Kim, Gon-Woo
    • The Journal of Korea Robotics Society
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    • v.11 no.1
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    • pp.33-40
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    • 2016
  • In this paper, we propose a method for estimating the pose of the camera using a rectangle feature utilized for the visual SLAM. A warped rectangle feature as a quadrilateral in the image by the perspective transformation is reconstructed by the Coupled Line Camera algorithm. In order to fully reconstruct a rectangle in the real world coordinate, the distance between the features and the camera is needed. The distance in the real world coordinate can be measured by using a stereo camera. Using properties of the line camera, the physical size of the rectangle feature can be induced from the distance. The correspondence between the quadrilateral in the image and the rectangle in the real world coordinate can restore the relative pose between the camera and the feature through obtaining the homography. In order to evaluate the performance, we analyzed the result of proposed method with its reference pose in Gazebo robot simulator.

An egornomic study on visual accomodation and pupil functions during the observation of binocular 3-D images (이안식 입체영상 관찰자 조절과 공동기능에 관한 인간공학적인 연구)

  • Cho, Am
    • Journal of the Ergonomics Society of Korea
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    • v.11 no.1
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    • pp.3-12
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    • 1992
  • To put the binocular 3-D images system into practical use, it is required to investigate the relationship between the system and men and to make ergonomic evaluation of the system. In this study, we perform a comparative analysis of the changes in the accommodation and pupil functions before and afer observing binocular 3-D images a sthe visual distance varies. From the experiment, we obtained the following results: (1) The discordance in the distance informatioons on the accommodation and pupil functions when obwerving 3-D images is compensated by the miosis and altering the focal depth. (2) From the consideration of the effect of the visual distance condition on the visual functions, it is thoughth that the visual functions are stabilized at the dark focus in the sense that the changes in the tension and relazation afer observing the 3-D images are minimized.

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Clinical Estimation of Corrected State with Change in Vertex Distance (정점간거리 변화에 따른 교정상태의 임상 평가)

  • Kim, Jung-Hee;Lee, Hak-Jun
    • Journal of Korean Ophthalmic Optics Society
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    • v.15 no.1
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    • pp.25-30
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    • 2010
  • Purpose: This study was conducted to estimate the changes of corrected diopter and corrected visual acuity with the change in vertex distance. Also we aimed to provide basic data for refraction test. Methods: Using the trial lens, we measured the corrected diopter and corrected visual acuity after performing binocular balance test. We measured the changes of corrected diopter and corrected visual acuity in change of vertex distance. We analyzed statistical significance and relations between vertex distance and corrected diopter and corrected visual acuity. Results: There was no difference in corrected diopter with the change of vertex distance within -1.00D, but the corrected diopter increased with it over - 1.25D. In particular, the change of diopter was largest when the vertex distance increased 15 mm. At over 11.00D, there was large changes of diopter with the changes of vertex distance at 5 mm, 10 mm and 15 mm. On correlation analysis between the vertex distance and the corrected diopter, there was strong correlation (r=0.999 at 5 mm increase of vertex distance, r=0.982 at 10 mm increase and r=0.957 at 15 mm increase) and also there was significant (p<0.01). At the change of visual acuity in increased of vertex distance, the range of a decrease in visual acuity was large when the changes of vertex distance was largest. On correlation analysis between the vertex distance and the corrected visual acuity, there was strong correlation (r=0.969 at 5 mm increase of vertex distance, r=0.985 at 10 mm increase and r=0.994 at 15 mm increase) and also there was significant (p<0.01). Conclusions: The vertex distance was very important at the refraction test and at wearing spectacle. On correlation analysis between the vertex distance and the corrected diopter, and the corrected visual acuity, there was strong correlation and statistically significant. Therefore, the vertex distance should be kept at the refraction using trial lens, and the best fitting was made not to slipping forward, and so we suggested regular refitting of spectacle and the managing method of spectacle were educated to the spectacle wearers.