• Title/Summary/Keyword: Visual Research Method

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UGR Detection and Tracking in Aerial Images from UFR for Remote Control (비행로봇의 항공 영상 온라인 학습을 통한 지상로봇 검출 및 추적)

  • Kim, Seung-Hun;Jung, Il-Kyun
    • The Journal of Korea Robotics Society
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    • v.10 no.2
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    • pp.104-111
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    • 2015
  • In this paper, we proposed visual information to provide a highly maneuverable system for a tele-operator. The visual information image is bird's eye view from UFR(Unmanned Flying Robot) shows around UGR(Unmanned Ground Robot). We need UGV detection and tracking method for UFR following UGR always. The proposed system uses TLD(Tracking Learning Detection) method to rapidly and robustly estimate the motion of the new detected UGR between consecutive frames. The TLD system trains an on-line UGR detector for the tracked UGR. The proposed system uses the extended Kalman filter in order to enhance the performance of the tracker. As a result, we provided the tele-operator with the visual information for convenient control.

Visual-Attention-Aware Progressive RoI Trick Mode Streaming in Interactive Panoramic Video Service

  • Seok, Joo Myoung;Lee, Yonghun
    • ETRI Journal
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    • v.36 no.2
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    • pp.253-263
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    • 2014
  • In the near future, traditional narrow and fixed viewpoint video services will be replaced by high-quality panorama video services. This paper proposes a visual-attention-aware progressive region of interest (RoI) trick mode streaming service (VA-PRTS) that prioritizes video data to transmit according to the visual attention and transmits prioritized video data progressively. VA-PRTS enables the receiver to speed up the time to display without degrading the perceptual quality. For the proposed VA-PRTS, this paper defines a cutoff visual attention metric algorithm to determine the quality of the encoded video slice based on the capability of visual attention and the progressive streaming method based on the priority of RoI video data. Compared to conventional methods, VA-PRTS increases the bitrate saving by over 57% and decreases the interactive delay by over 66%, while maintaining a level of perceptual video quality. The experiment results show that the proposed VA-PRTS improves the quality of the viewer experience for interactive panoramic video streaming services. The development results show that the VA-PRTS has highly practical real-field feasibility.

Improved Viewing Quality of 3-D Images in Computational Integral Imaging Reconstruction Based on Round Mapping Model

  • Shin, Dong-Hak;Kim, Nam-Woo;Yoo, Hoon;Lee, Joon-Jae;Lee, Byoung-Ho;Kim, Eun-Soo
    • ETRI Journal
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    • v.29 no.5
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    • pp.649-654
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    • 2007
  • In this paper, we propose a computational integral imaging reconstruction (CIIR) method using a round mapping model to improve the viewing quality of 3-D images. The proposed CIIR method can overcome the problem of non-uniformly reconstructed images caused by the conventional method. To show the usefulness of proposed method, some experiments are carried out and the results are presented.

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A study on the methods of inquiry in the history of costume (복식사연구방법에 관한 소고(ll))

  • 신상옥
    • Journal of the Korean Home Economics Association
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    • v.23 no.4
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    • pp.9-17
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    • 1985
  • The pur[pose of this study is to investigate the research method and to provide a guide to the ways in which researcher, interested in costume history, can obtain in formation. There are comparison, induction, observation, awnalysis, experience and synthesis in method of science. Firstly, comparative research is to ascertain the accumulated evidence. Secondly, we can compare with historical phenomenon. A research intend to verify the hypothesis based upon the sources of information. It is an available method to investigate the costumes and adornments in the past. Whatever the approach, the researcher much discribe the facts objectively. Historical research has been approached in many warys in the field of costume. There are visual and documentary sources. Visual sources are paintings, sculptutre, frescoes, coins, potteries, medals, mosaics, wall paintings, stained glasses, seals, tapestries, illustrations, photographs, movies, and fashion dolls. Documentary sources are archives, letters, diaries, literature, wardrobe accounts, sumpturary laws, newspapers, and recollections.

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An Effective Moving Cast Shadow Removal in Gray Level Video for Intelligent Visual Surveillance (지능 영상 감시를 위한 흑백 영상 데이터에서의 효과적인 이동 투영 음영 제거)

  • Nguyen, Thanh Binh;Chung, Sun-Tae;Cho, Seongwon
    • Journal of Korea Multimedia Society
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    • v.17 no.4
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    • pp.420-432
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    • 2014
  • In detection of moving objects from video sequences, an essential process for intelligent visual surveillance, the cast shadows accompanying moving objects are different from background so that they may be easily extracted as foreground object blobs, which causes errors in localization, segmentation, tracking and classification of objects. Most of the previous research results about moving cast shadow detection and removal usually utilize color information about objects and scenes. In this paper, we proposes a novel cast shadow removal method of moving objects in gray level video data for visual surveillance application. The proposed method utilizes observations about edge patterns in the shadow region in the current frame and the corresponding region in the background scene, and applies Laplacian edge detector to the blob regions in the current frame and the corresponding regions in the background scene. Then, the product of the outcomes of application determines moving object blob pixels from the blob pixels in the foreground mask. The minimal rectangle regions containing all blob pixles classified as moving object pixels are extracted. The proposed method is simple but turns out practically very effective for Adative Gaussian Mixture Model-based object detection of intelligent visual surveillance applications, which is verified through experiments.

A Modified Length-Based Grading Method for Assessing Coronary Artery Calcium Severity on Non-Electrocardiogram-Gated Chest Computed Tomography: A Multiple-Observer Study

  • Suh Young Kim;Young Joo Suh;Na Young Kim;Suji Lee;Kyungsun Nam;Jeongyun Kim;Hwan Kim;Hyunji Lee;Kyunghwa Han;Hwan Seok Yong
    • Korean Journal of Radiology
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    • v.24 no.4
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    • pp.284-293
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    • 2023
  • Objective: To validate a simplified ordinal scoring method, referred to as modified length-based grading, for assessing coronary artery calcium (CAC) severity on non-electrocardiogram (ECG)-gated chest computed tomography (CT). Materials and Methods: This retrospective study enrolled 120 patients (mean age ± standard deviation [SD], 63.1 ± 14.5 years; male, 64) who underwent both non-ECG-gated chest CT and ECG-gated cardiac CT between January 2011 and December 2021. Six radiologists independently assessed CAC severity on chest CT using two scoring methods (visual assessment and modified length-based grading) and categorized the results as none, mild, moderate, or severe. The CAC category on cardiac CT assessed using the Agatston score was used as the reference standard. Agreement among the six observers for CAC category classification was assessed using Fleiss kappa statistics. Agreement between CAC categories on chest CT obtained using either method and the Agatston score categories on cardiac CT was assessed using Cohen's kappa. The time taken to evaluate CAC grading was compared between the observers and two grading methods. Results: For differentiation of the four CAC categories, interobserver agreement was moderate for visual assessment (Fleiss kappa, 0.553 [95% confidence interval {CI}: 0.496-0.610]) and good for modified length-based grading (Fleiss kappa, 0.695 [95% CI: 0.636-0.754]). The modified length-based grading demonstrated better agreement with the reference standard categorization with cardiac CT than visual assessment (Cohen's kappa, 0.565 [95% CI: 0.511-0.619 for visual assessment vs. 0.695 [95% CI: 0.638-0.752] for modified length-based grading). The overall time for evaluating CAC grading was slightly shorter in visual assessment (mean ± SD, 41.8 ± 38.9 s) than in modified length-based grading (43.5 ± 33.2 s) (P < 0.001). Conclusion: The modified length-based grading worked well for evaluating CAC on non-ECG-gated chest CT with better interobserver agreement and agreement with cardiac CT than visual assessment.

Assistive Technologies (AT) Preferences of People Living with Visual Disability as Information Access Tools in Academic Libraries

  • Adefunke Olanike Alabi;Olatokunbo Christopher Okiki
    • International Journal of Knowledge Content Development & Technology
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    • v.13 no.2
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    • pp.35-50
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    • 2023
  • Assistive technologies are necessary for ensuring independent living and equal participation in an information-based society for people living with disabilities (PLWD). This study investigated the assistive technology preference of students with visual disabilities, and the approach academic libraries should adopt in procuring assistive technologies. The study adopted a quantitative research method, with a survey as the research design. The study was conducted among visually disabled students in four public universities in Nigeria. Using the total enumeration method, an online questionnaire was used to obtain information from 151 students who voluntarily agreed to partake in the survey. The study found that access to electronic resources, scanning/conversion of print resources to electronic formats and access to information on the Web were among the technology-based services provided to visually disabled students. COBRA, ZoomText, Supernova and Dragon Naturally Speaking are the most preferred assistive technologies (software). At the same time, handheld scanners ($\bar{x}=4.40$) and braille keyboards ($\bar{x}=4.60$) are the most preferred assistive technologies in the hardware category by visually challenged students. The study further revealed that the library management should consult with students living with a visual disability before procuring assistive technology. Findings from this study thus provide further evidence of the need for librarians to fulfil their moral and legal obligation in advocating the provision of assistive technologies. Library administrators and university stakeholders should expedite actions on meeting the assistive technology needs of people living with visual disabilities. These actions should transcend mere policy formulation on the provision of assistive technologies to restructuring their services and spaces to accommodate assistive technologies as information service delivery tools for people with visual disabilities.

A Novel Visual Servoing Method involving Disturbance Observer (외란관측기를 이용한 새로운 시각구동방법)

  • Lee, Joon-Soo;Suh, Il-Hong;You, Bum-Jae
    • Proceedings of the KIEE Conference
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    • 1998.07g
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    • pp.2312-2314
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    • 1998
  • To improve the visual servoing performance, several strategies were proposed in the past such as redundant feature points, using a point with different height and weighted selection of image features. The performance of these visual servoing methods depends on the configuration between the camera and object. And redundant feature points require much computation efforts. This paper proposes the visual servoing m based on the disturbance observer, which compe the upper off-diagonal component of image fe Jacobian to be null. The performance indices su sensitivity for a measure of richness, sensitiv the control to noise, and controllability are sho improved when the image feature Jacobian is giv a block diagonal matrix. Computer simulation carried out for a PUMA560 robot and show results to verify the effectiveness of the pro method.

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Statistical study on the kinematic distribustion of coronal mass ejections from 1996 to 2015

  • Jeon, Seong-Gyeong;Moon, Yong-Jae;Yi, Kangwoo;Lee, Harim
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.61.4-62
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    • 2017
  • In this study we have made a statistical investigation on the kinematic classification of coronal mass ejections (CMEs) using about 4,000 SOHO/LASCO CMEs from 1996 to 2015. For this we use their SOHO/LASCO C3 data and exclude all poor events. Using the constant acceleration model, we classify these CMEs into three groups: Acceleration group, Constant Velocity group, and Deceleration group. For classification we adopt four different methods: Acceleration method, Velocity Variation method, Height Contribution method, and Visual Inspection method. Our major results are as follows. First, the fractions of three groups depend on the method used. Second, the results of the Height Contribution method are most consistent with those of the Visual Inspection method, which is thought to be most promising. Third, the fractions of different kinematic groups for the Height contribution method are: Acceleration (35%), Constant speed (47%), and Deceleration (18%). Fourth, the fraction strongly depend on CME speed; the fraction of Acceleration decreases from 0.6 to 0.05 with CME speed; the fraction of Constant increases from 0.3 to 0.7; the fraction of Deceleration increases from 0.1 to 0.3. Finally we present dozens of CMEs with non-constant accelerations. It is found that about 40 % of these CMEs show quasi-periodic oscillations.

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Visual Comfort Enhancement of Auto-stereoscopic 3D Display using the Characteristic of Disparity Distribution (시차 분포 특성을 이용한 오토스테레오스코픽 3차원 디스플레이 시청 피로도 개선 방법)

  • Kim, Donghyun;Sohn, Kwanghoon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.3
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    • pp.107-113
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    • 2016
  • Visual discomfort is a common problem in three-dimensional videos. Among the methods to overcome visual discomfort presented in current research, disparity adjustment methods provide little guidance in determining the condition for disparity control. We propose a diaprity adjustment based on the characteristics of disparity distribution on visual comfort, where the visual comfort level is used as the adjustment paramter, in parallax barrier type auto-stereoscopic 3D display. In this paper, we use the horizontal image shift method for disparity adjustment to enhance visual comfort. The speeded-up robust feature is used to estimate the disparity distribution of 3D sequences, and the required amount for disparity control is chosen based on the pre-defined characteristics of disparity distribution on visual comfort. To evaluate the performance of the proposed method, we used a 3D equipment. Subjective tests were conducted at the fixed optimal viewing distance. The results show that comfortable videos were generated based on the proposed disparity adjustment method.