• Title/Summary/Keyword: dynamic visual

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The Effect of Dynamic Visual-Motor Integration Training on the Visual Perception Reaction Velocity (역동적 시각-운동 통합 훈련이 시지각 처리 속도에 미치는 영향)

  • Song, Minok;Lee, Eunsil;Park, Sungho
    • Journal of The Korean Society of Integrative Medicine
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    • v.3 no.4
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    • pp.37-42
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    • 2015
  • Purpose: This study was conducted to test the impact of The Dynamic Visual-Motor integration training has effect on the visual perception reaction velocity. Dynavision were used to measure data from the participating 24 students(K college). Method : The participants were the 24 students of 'K' College in Busan in there twenties. They were divided into the The Dynamic Visual-Motor integration training group and the control group. To know if the Dynamic Visual-Motor integration training has effect on the visual perception reaction velocity, the Dynamic Visual-Motor integration training was implemented triweekly for 4 weeks. In Dynamic Visual-Motor integration training the ball should be grasped with one hand and threw by an arm. Only the balls threw beyond the objective point were counted. The visual perception reaction velocity and the number of response were measured before and after experiment by Dynavision. Result : Firstly, the visual perception reaction velocity was increased in Dynamic Visual-Motor integration training group compared with control group. Secondly, the number of response was also increased in Dynamic Visual-Motor integration training group compared with control group. Conclusion : As a result of The Dynamic Visual-Motor integration training has an effect on the visual perception reaction velocity and the number of response. The Dynamic Visual-Motor integration training seems to be effective for cerebral apoplexy patient who has visual perceptional disability or cerebral palsy child in training for visual perceptional development or daily living activities development. Study participated by more detailed and practical patients in hospital is needed.

A New Feature-Based Visual SLAM Using Multi-Channel Dynamic Object Estimation (다중 채널 동적 객체 정보 추정을 통한 특징점 기반 Visual SLAM)

  • Geunhyeong Park;HyungGi Jo
    • IEMEK Journal of Embedded Systems and Applications
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    • v.19 no.1
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    • pp.65-71
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    • 2024
  • An indirect visual SLAM takes raw image data and exploits geometric information such as key-points and line edges. Due to various environmental changes, SLAM performance may decrease. The main problem is caused by dynamic objects especially in highly crowded environments. In this paper, we propose a robust feature-based visual SLAM, building on ORB-SLAM, via multi-channel dynamic objects estimation. An optical flow and deep learning-based object detection algorithm each estimate different types of dynamic object information. Proposed method incorporates two dynamic object information and creates multi-channel dynamic masks. In this method, information on actually moving dynamic objects and potential dynamic objects can be obtained. Finally, dynamic objects included in the masks are removed in feature extraction part. As a results, proposed method can obtain more precise camera poses. The superiority of our ORB-SLAM was verified to compared with conventional ORB-SLAM by the experiment using KITTI odometry dataset.

Differences of Dynamic Visual Acuity According to Optical Lens Color (안경렌즈 색상에 따른 동체 시력의 변화)

  • Lee, Min-A;Kim, Young Ji;Jeong, Ju-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.1
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    • pp.7-11
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    • 2011
  • Purpose: The purpose of this study is to investigate the differences of dynamic visual acuity to color of optical lens. Methods: we measured dynamic visual acuity using 5 colored lenses (transparent, yellow, blue, green, brown) for 30 university students. Results: Dynamic visual acuity were highest on yellow colored lens and lowest on brown colored lens, for both of naked eyes and contact lens wearers. Conclusions: It can be concluded that optical lens color can influence on dynamic visual acuity. Selection of colour lense can enhance or decrease of dynamic visual acuity. Therefore, a selection of colour lense should be carefully decided especially for athletes who needs a good dynamic visual acuity.

Semantic Visual Place Recognition in Dynamic Urban Environment (동적 도시 환경에서 의미론적 시각적 장소 인식)

  • Arshad, Saba;Kim, Gon-Woo
    • The Journal of Korea Robotics Society
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    • v.17 no.3
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    • pp.334-338
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    • 2022
  • In visual simultaneous localization and mapping (vSLAM), the correct recognition of a place benefits in relocalization and improved map accuracy. However, its performance is significantly affected by the environmental conditions such as variation in light, viewpoints, seasons, and presence of dynamic objects. This research addresses the problem of feature occlusion caused by interference of dynamic objects leading to the poor performance of visual place recognition algorithm. To overcome the aforementioned problem, this research analyzes the role of scene semantics in correct detection of a place in challenging environments and presents a semantics aided visual place recognition method. Semantics being invariant to viewpoint changes and dynamic environment can improve the overall performance of the place matching method. The proposed method is evaluated on the two benchmark datasets with dynamic environment and seasonal changes. Experimental results show the improved performance of the visual place recognition method for vSLAM.

Dynamic Visual Acuity and Dynamic Stereoacuity of Athletes and Nonathletes (운동선수와 대학생 남녀의 동체 시력 및 동적 입체시에 관한 비교 연구)

  • Lee, Min-A;Oh, Jae-Man;Jung, Ju-Hyun
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.3
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    • pp.43-49
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    • 2009
  • Purpose: The purpose of this study was to obtain the fundamental data of dynamic visual acuity and dynamic stereoacuity. Methods: The subjects were 20 athletes (high school baseball player) and 40 nonathletes (20 male, 20 female). We assessed static visual acuity, dynamic visual acuity, static stereoacuity and dynamic stereoacuity using rotating mirror projection system and computer program. Results: Three groups had similar static visual acuity and static stereoacuity. On the other hand, the dynamic visual acuity and dynamic stereoacuity showed statistically significant differency. The mean dynamic visual acuity for athletes was 174.80${\pm}$28.70 deg/sec, 137.10${\pm}$16.54 deg/sec for male nonathletes and 111.59${\pm}$15.40 deg/sec for female nonathletes. The mean dynamic stereoacuity for athlets was 234.55${\pm}$19.64, 249.05${\pm}$8.86 for male nonathletes and 247.10${\pm}$14.89 for female nonathletes. The group of athletes had better dynamic visual acuity and dynamic stereoacuity. Conclusions: If the result of this study apply to sports, it will be very useful to improve sports performance.

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Investigating Arithmetic Mean, Harmonic Mean, and Average Speed through Dynamic Visual Representations

  • Vui, Tran
    • Research in Mathematical Education
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    • v.18 no.1
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    • pp.31-40
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    • 2014
  • Working with dynamic visual representations can help students-with-computer discover new mathematical ideas. Students translate among multiple representations as a strategy to investigate non-routine problems to explore possible solutions in mathematics classrooms. In this paper, we use the area models as new representations for our secondary students to investigate three problems related to the average speed of a particle. Students show their ideas in the process of investigating arithmetic mean, harmonic mean, and average speed through their created dynamic figures. These figures really utilize dynamic geometry software.

Stereo Vision-based Visual Odometry Using Robust Visual Feature in Dynamic Environment (동적 환경에서 강인한 영상특징을 이용한 스테레오 비전 기반의 비주얼 오도메트리)

  • Jung, Sang-Jun;Song, Jae-Bok;Kang, Sin-Cheon
    • The Journal of Korea Robotics Society
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    • v.3 no.4
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    • pp.263-269
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    • 2008
  • Visual odometry is a popular approach to estimating robot motion using a monocular or stereo camera. This paper proposes a novel visual odometry scheme using a stereo camera for robust estimation of a 6 DOF motion in the dynamic environment. The false results of feature matching and the uncertainty of depth information provided by the camera can generate the outliers which deteriorate the estimation. The outliers are removed by analyzing the magnitude histogram of the motion vector of the corresponding features and the RANSAC algorithm. The features extracted from a dynamic object such as a human also makes the motion estimation inaccurate. To eliminate the effect of a dynamic object, several candidates of dynamic objects are generated by clustering the 3D position of features and each candidate is checked based on the standard deviation of features on whether it is a real dynamic object or not. The accuracy and practicality of the proposed scheme are verified by several experiments and comparisons with both IMU and wheel-based odometry. It is shown that the proposed scheme works well when wheel slip occurs or dynamic objects exist.

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Effect of Motor Imagery Training with Visual and Kinesthetic Imagery Training on Balance Ability in Post Stroke Hemiparesis (시각적인 상상연습 훈련과 운동 감각적인 상상연습 훈련이 편마비 환자의 균형능력에 미치는 영향)

  • Kim, Jin-Seop;Kim, Kyoung
    • Journal of the Korean Society of Physical Medicine
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    • v.5 no.4
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    • pp.517-525
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    • 2010
  • Purpose : This study aimed to compare the effect of two conditions (visual and kinesthetic) of motor imagery training on static and dynamic balance. Methods : Fifteen patients with post-stroke hemiparesis volunteered to participate in this study. Two motor imagery training conditions, for 10minute trials, employed with audiotape instructions. Measurements were performed at pretest, posttest and 1-hour follow up in both static and dynamic balance. Results : Measures were significantly different both static and dynamic balance tests between treatment conditions (kinesthetic imagery more than visual imagery) at the pretest, post test, and 1-hour follow-up (p<.05). Measures of both static and dynamic balance tests, for both conditions, improved significantly from pretest to posttest (p<.05), and was maintained at 1-hour follow up. Conclusion : This study showed that both imagery training applications were effective treatment strategies for both static and dynamic balance. When comparing the two treatment conditions, kinesthetic motor imagery training was more effective than the visual motor imagery training in static and dynamic balance.

Implementation of dynamic visual acuity testing system using optical see through head mounted display

  • Son, Hojun;Yun, Deokyoung;Kim, Jungho;Lee, Seunghyun;Kwon, Soonchul
    • International Journal of Internet, Broadcasting and Communication
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    • v.9 no.3
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    • pp.70-77
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    • 2017
  • Dynamic visual acuity is used as an important factor to measure athletic performance in sports field. A study on visual acuity testing system using non-see head mounted display (NST-HMD) was conducted recently. However, the NST-HMD has a problem that the sense of space felt by the subject differs from the actual environment. This is because the view is blocked so that it is only implemented in a virtual space. This paper proposes a dynamic visual acuity testing system using optical see through head mounted display (OST-HMD). To do this, OST-HMD and NST-HMD comparative tests were conducted using existing K-D (King-Devick) charts. Experiments were performed on 30 subjects and their visual acuity was measured and analyzed by parametric statistics and one-sample T-test. The results of the study demonstrate the effectiveness of the proposed OST-HMD. This study is expected to use the visual inspection and training equipment of OST-HMD.

Construction of the 2D General $\Delta-TABLE$ of the Numerical Series of Position for the Syntactical Semantics of Visual Space (시(視)공간의 통사의미론을 위한 위치수열 2차원 일반 $\Delta-TABLE$의 구성)

  • Kim Bok-Young
    • Journal of Science of Art and Design
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    • v.2
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    • pp.239-293
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    • 2000
  • The paper aims to study how to describe the rigorous position on which semantic elements are laid, within the visual space. This purpose is, first of all, for the construction of visual syntactical semantics of the visual space. For this aim, the preliminary research begins with some definitions on : 1) visual space, visual design, visual syntactical semantic meaning, 2) position, sequence of position, 2-dim. sequence of position, and 3) 2-dim. numerical series of position, harmonious dynamic values. Here, The main issue is to define the position in general. To solve this problem, the researcher surveyed the positions on which the sets of pixemes are set up. The results are as follows ; 1. As far as the positions in visual space are concerned, they are the possible locations permitted in the visual patches. They are not the factual but the possible positions. 2.The position value that the sequential point has is not arithmetical but harmonious-dynamic, for it is not permitted for its own sake, but for the person, that is to say, for the viewer's visual perception. 3. The harmonious-dynamic value of positional sequence can be composed of the 2-dimensional successive numerical series which is, in turn, composed of the primordial 3 values x0, $\mu0$, y0. Here, the $\mu0$ is the harmonious mean value of x0 and y0. The x0 and y0 are, therefore, of the mutual dynamic relationship. 4. From this, the 2-dim general $\Delta-TABLE$ of the numerical series of position in visual design could be acquired through development of the primordial 3 values into the $X_i,\;Y_i$, orbit values.

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