• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.12
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• pp.2498-2504
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• 2009

The fundamental research for the mobile robot navigation using the numerical optimization method is presented. We propose an image-based visual servo navigation algorithm for a wheeled mobile robot utilizing a ceiling mounted camera. For the image-based visual servoing, we define the composite image Jacobian which represents the relationship between the speed of wheels of a mobile robot and the robot's overall speed in the image plane. The rotational speed of wheels of a mobile robot can be directly related to the overall speed of a mobile robot in the image plane using the composite image Jacobian. We define the mobile robot navigation problem as an unconstrained optimization problem to minimize the cost function with the image error between the goal position and the position of a mobile robot. In order to avoid the obstacle, the modified cost function is proposed which is composed of the image error between the position of a mobile robot and the goal position and the distance between the position of a mobile robot and the position of the obstacle. The performance was evaluated using the simulation.

• Journal of the Ergonomics Society of Korea
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• v.27 no.4
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• pp.1-8
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• 2008

Objective: This study is to analyze the factor affecting elderly's speed of mobile phone ability. Method: Sixty healthy senior citizens who live in Kim-hye participated in Cognition, Visual perception, Speed of mobile phone ability and the collected data was analyzed by an independent multiple regression analysis. Result: The findings can be summarized as follows; 1. Although men were faster than women while using mobile phone, there was little satisfical significance(p<0.05). 2. Although people in their sixties were faster than people in their seventies while using mobile phone, there was minial difference(p<0.05). 3. The primary factor which affect mobile phone using speed is figure ground, visual memory, visual processing and the most beneficial discovery in the entire project is figure ground(p<0.05). Conclusion: The result of study showed that in order to enhance figure ground, visual memory, visual processing in mobile phone using speed. These results will be consider useful for elderly's mobile phone ability.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.2
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• pp.337-339
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• 2020

Speed-run is a gameplay style in what the player tries to finish the game as quickly as possible. The purpose of this study is to observe and analyze the difference between a normal player and a speed runner in a speed run to better understand their interaction with the game and to extrapolate the applications of the analyzed frameworks to scenarios that extent normal gameplay. For this purpose, MDA (Mechanic, Dynamic, Aesthetics) and DPE (Experience, Design, Play) were used. As a result, the average player was found to focus on aesthetics or affects while the speed runner focused on mechanics and gameplay.

• Journal of the Korean Home Economics Association
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• v.42 no.10 s.200
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• pp.79-89
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• 2004

This study was designed to investigated children's spatial cognitive skills as based on their practice with computer games. The sixty children were divided into 3 groups there were twenty children in experimental group 1 (the geometric game experimental group), twenty children in experimental group 2 (the arcade game experimental group), and twenty children in the control group. The sSpatial cognitive skills of the children were assessed according to by visual speed, mental rotation, and spatial visualization tasks. The rResults showed that computer game practice enhanced the children's spatial skills (visual speed, mental rotation and, spatial visualization). The c Children's mental rotation and spatial visualization showed a significant difference with the type of computer game.

• Journal of the Semiconductor & Display Technology
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• v.11 no.3
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• pp.39-44
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• 2012

Electronics in modern lives have become more miniaturized and precise. Multi Layered Ceramic Capacitor (MLCC) occupies 50% of electronic components consisting of electronics. This high volume of the production needs high speed and more precise machine performances. The dominate parts of the production equipments are the module transporting components and the visual inspection module. Most visual inspection has been off-line because of the image processing time. In this paper, a new image processing method is proposed to reduce thousands of matrix calculation for image processing and realize on-line high speed inspection.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.31 no.2
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• pp.1-6
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• 2023

When landing an aircraft descent-speed, wind around the airport, and regulations are important indicators for the pilot to decide whether to land in the Final Approach. In this study, in order to maintain a decent angle accessible to the airport, the pilot predicts an appropriate decent rate suitable for wind direction, wind speed, and speed to make a stable landing. To confirm this, the decent rate according to the speed and speed of wind was calculated using the information actually measured on the B737NG aircraft and compared with the theoretical figures. The purpose of this study is to ensure that the pilot can make a stable landing at a given FPM (Feet Per Minute) when a visual approach and non-normal approach is required at an airport designed with a somewhat higher descent angle.

• Journal of Ship and Ocean Technology
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• v.10 no.4
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• pp.34-48
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• 2006

The visual observation of wave condition depends on the observer's skill and experience. Also, the environmental conditions such as light and cloud heavily influence the visual measurement. In the speed test of sea trial, the wave measurement should be objective and accurate. In this paper, the problems of visual measurement and their effects on speed test are described. To overcome those problems, we developed the wave measurement system using commercial marine X-band radar, WaveFinder. The system installed at inland base was calibrated by waverider buoy and then the system's operability was defined. Onboard tests had also been performed three times for formal wave measurement to correct the ship speed. The results illustrated very good agreement with visual observation by experts. It can be concluded that the system would be useful to measure wave and swell information for the sea trial, irrespective of day and night.

• Journal of Korea Entertainment Industry Association
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• v.15 no.1
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• pp.221-228
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• 2021

This study aims to provide basic data for developing hand functional training programs using a keyboard to see if there is a relationship between the smart keyboard input speed using both hands, the Dexterity of the hand and the eye-hand coordination ability. The smartphone keyboard input speed, Purdue Pegboard, Grooved Pegboard Test, and Korean-Developmental-Test of Visual Perception-Adolescent were evaluated for 40 university students Province. An independent sample t-test and one-way ANOVA were conducted to identify differences in smartphone keyboard input speed, dexterity, eye-hand coordination ability and visual-motion using both hands according to the general characteristics of the subjects. Pearson correlation was also conducted to find out the relationship between hand-used smartphone keyboard input speed, hand dexterity, eye-hand coordination ability and visual-motor. As a result, the smartphone keyboard input speed using both hands showed a correlation with the dominant hand in the Purdue Pegboard Test (r=-.313, p<.05). In addition, the input speed of the smartphone keyboard is Copying(r=-.333, p<.05), Visual Motor Search(r=.455, p<.01), Visual Motor speed(r=-.453, p<.01) and Form Constancy (r=-.341, p<.05) in the item of K-DTVP-A. Therefore, it is believed that it will be helpful in the development of a treatment program using a smartphone, and it is expected that the effectiveness of a treatment program using a smartphone will be proven through additional experimental studies in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.1
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• pp.247-253
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• 2012

The purpose of this study was to evaluate the effects of a visual flow speed's modulation-based VR(virtual reality) program on gait function in stroke patients. Thirty one stroke patients were randomly selected at Dep. of Rehabilitation medicine of M hospital in Seoul. We carried out the gait analysis by dividing them with four conditions : one condition had applied without the visual flow modulation-based VR and another had done three visual flow speed's modulation-based VR(0.25, 1, 2 times). The gait analysis was used with GaitRite system. The data were collected using gait velocity, cadence, stride length, step length, single support time, and double support time during treatment. The results were as follows. First, the slow visual flow(0.25 times)-based VR program on the condition was significant decrease gait velocity, cadence, stride length, step length and increase single support time, double support time(p<.05). Second, the fast visual flow(2 times)-based VR program on the condition was significant increase gait velocity, cadence, stride length, step length, single support time on paretic lower limb and decrease single support time on non-paretic lower limb, double support time(p<.05). Third, the normal visual flow(1 times)-based VR program on the condition was not significant differ gait velocity, cadence, stride length, step length, single support time, double support time. In conclusion, the visual flow speed's modulation-based VR program improves gait function in chronic stroke patients.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.2
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• pp.93-103
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• 2019

This study analyzed the impact of smartphone usage on walking speed during walking on two pedestrian walkways in Daejeon Metropolitan City. For the analysis, the video data about the actual use of smartphone was acquired and the walking speed was calculated based on the walking density of the pedestrian Level Of Service(LOS) presented in the Road Capacity Manual. Multiple regression analysis and decision tree using machine learning were used to analyze the impact of smartphone usage on walking speed, and as the explanatory variables, gender, disable smartphone, use of smartphone using auditory function, use of smartphone using visual function, LOS A, LOS B, LOS C were adopted. The result showed that LOS C had the highest impact on walking speed change and the women's group using their visual function was founded to have the slowest walking speed in LOS C. In particular, the author found that walking speed significantly decreased in the case of use of visual function rather than listening to music or the hearing on the phone.