• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.10
• /
• pp.82-88
• /
• 2003

Many visual servoing algorithms have been recently developed by the robot vision researchers. They do not, however, consider the stability of servoing system. The camera calibration is the most important factor to the control stability and performance of position based visual servoing. In this article we describe the ECL(End Point Closed Loop) servoing can make no steady state error for the control of 6-DOF robot of which accuracy is dependent on the camera calibration and kinematics. And we propose a dynamic calibration algorithm, which can improve stability and performance of ECL visual servoing. To verify the potential of our approach, we run assembly experiments and present our finding.

• 전기의세계
• /
• v.21 no.5
• /
• pp.7-12
• /
• 1972

Applying the theory of physiology and control systems, the visual system was studied as a regulator of impining light. The characteristics function of visual system is mainly analysed by spato-temporal characteristics based upon Enroth's model, Broca-Sulzer phenomenon and Mach effect. Some aims of this paper are as follows. (1) In order to get the excitatory and inhibitory potential of the intermediated cell layer in the retina, the exponential value, {exp(FM/kT)- $I_{mn}$ } is caculated based on the physiological theory in neuro-phenomena. (2) To show the visual characteristics by analog simulation for generating stimulus waveforms and analysis, the visual adaptation was recorded as electrical stimulation in the form of step functions. Furthermore, ti is shown that the above experimental data agrees satisfactorily with the theoretical (psychophysiological) values. This study is expected to lead to further studies concerned with human observer and human operator in control and especially pattern recognition systems.stems.

• Electrical & Electronic Materials
• /
• v.8 no.5
• /
• pp.551-557
• /
• 1995

For the observation of treeing, a visual measurement with an optical microscope has been used to explain breakdown mechanism in high-voltage systems. The conventional directed visual method of tree aging observation is difficult to measure in short time processing, and it is impossible to analyze on tree degradation area, progressed direction, tree pattern, etc. By using an image processing technique, the tree features which appear immediately after the tree initiation as well as changes in the configuration of the tree can be easily measured and observed than using the conventional visual methods. In this paper, we have developed a tree observating system by using image processing for tree growth, degradation area and other treeing progress. As an experimental result, it can be concluded that the image processing method is a more effective alternative than directed visual observation method. As a matter of fact, it is possible to record the image of tree propagation immediately after its first appearance and explain the characteristics of tree growth froth the computer processing image.

• Journal of Biomedical Engineering Research
• /
• v.15 no.1
• /
• pp.57-62
• /
• 1994

The demand of image compression is increasing now for the integration of medical images into the hospital information system. Even though the quantitative distortion can be measured from the difference between original and reconstructed images, it doesn't include the nonlinear characteristics of human visual system. In this study, we have evaluated the nonlinear characteristics of human visual system and applied them to the compression of medical images. The distortion measures which reflect the characteristics of human visual system has been considered. This image compression procedure consists of coding scheme using JND (Just Noticeable Difference) curve, polynomial approximation and BTC (Block Truncation Coding). Results show that this method can be applied to CT images, scanned film images and other kinds of medical images with the compression ratio of 5-10:1 without any noticeable distortion.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
• /
• v.8 no.2
• /
• pp.72-77
• /
• 2009

A number of new DTV technologies have been introduced to provide crystal clear picture and enhanced sound. HDTV, in particular has four times resolution of conventional TV along with 16:9 aspect ratio. Also the introduction of the new technologies offered a valuable basis for character graphics which was only an assistant method to deliver visual images effectively. Various sizes of displays for different applications such as high definition TV and mobile multimedia services have created demands for additional features of character graphics including proper letter fonts, colors, moving effects as much. This article analyzes in what way the visual elements above can affect uses' visual perception. New CG formats designed for OSMU, one source multi use, are also suggested available to each media. For the research three groups of CG designers, art directors and productions/distribution groups are established according to production process by two Delphi surveys of TV production staff.

• Journal of information and communication convergence engineering
• /
• v.10 no.3
• /
• pp.300-306
• /
• 2012

An image attention model and its application to image quality assessment are discussed in this paper. The attention model is based on rarity quantification, which is related to self-information to attract the attention in an image. It is relatively simpler than the others but results in taking more consideration of global contrasts between a pixel and the whole image. The visual attention model is used to develop a local distortion predictor, named color visual differences predictor (CVDP), in color images in order to effectively detect luminance and color distortions.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.26 no.5
• /
• pp.594-605
• /
• 2002

The purpose of this study is to investigate the visual sensibility of wedding dress. There are 28 kinds of costume samples from photographs in wedding dress magazines. They were divided into simple, accent and decorative design. The Semantic Differential method was used in this study to measure them. The semantic scale was composed of 20 pairs of adjective words. The data were analyzed by factor analysis, ANOVA, MDS and regression analysis. The results are as follow; 1. Factor analysis has extracted five factors which consist of the visual sensibility of wedding dress. The factors are High quality, Cuteness, Femininity, Decoration and Modernness. 2. There were significant differences in the visual sensibility of wedding dress and demographics.3. The evaluative dimensions of the visual sensibility of wedding dress were identified by Cute-Adult and Simple-Decorative. 4. Preference was related to what are wearing-desirable, chic, cute, natural and beautiful, etc., and the wearing desire was related to what are favorite, lively, chic, special and gracious, etc. The noble sensibility was related to what are elegant, cute, feminine and chic, etc.

• Journal of Power System Engineering
• /
• v.6 no.1
• /
• pp.96-101
• /
• 2002

In this paper, we address the problem of controlling an end-effector to track and grab a moving target using the visual servoing technique. A visual servo mechanism based on the image-based servoing principle, is proposed by using visual feedback to control an end-effector without calibrated robot and camera models. Firstly, we consider the control problem as a nonlinear least squares optimization and update the joint angles through the Taylor Series Expansion. And to track a moving target in real time, the Jacobian estimation scheme(Dynamic Broyden's Method) is used to estimate the combined robot and image Jacobian. Using this algorithm, we can drive the objective function value to a neighborhood of zero. To show the effectiveness of the proposed algorithm, simulation results for a six degree of freedom robot are presented.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.5 no.2
• /
• pp.390-407
• /
• 2011

Three-dimensional (3D) video technologies are becoming increasingly popular, as it can provide users with high quality and immersive experiences. However, color inconsistency between the camera views is an urgent problem to be solved in multi-view imaging. In this paper, a perception-based color correction method for multi-view images is proposed. In the proposed method, human visual sensitivity (VS) and visual attention (VA) models are incorporated into the correction process. Firstly, the VS property is used to reduce the computational complexity by removing these visual insensitive regions. Secondly, the VA property is used to improve the perceptual quality of local VA regions by performing VA-dependent color correction. Experimental results show that compared with other color correction methods, the proposed method can greatly promote the perceptual quality of local VA regions greatly and reduce the computational complexity, and obtain higher coding performance.

• Journal of Biomedical Engineering Research
• /
• v.15 no.2
• /
• pp.135-142
• /
• 1994

This paper presents average method to detect Visual-Transient Evoked Potential from the human scalp electric potential measured by the ElectroEncephaloGram. To confirm the validity of average method, the average-process is performed with both stimulated and no-stimulated potentials respectively, and both results are compared. The specific waveform, which is visual-transient evoked potential, is produced only in the case of stimulated potential. It was found that a dc-drift, due to instrumentation errors and other noises, can produce significant changes in the evoked-potential waveform. This can be removed with a high-pass filter (cut-off frequency=0.5Hz).