• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.956-964
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• 2017

This study contributes to deepening understand of the characteristics of fishing vessel rolling motions to improve the development of capsizing alarm systems. A time domain rolling motion simulation was performed. In order to verify capsizing alarm systems, it is necessary to carry out experiments assuming a capsizing situation and perform actual fishing vessel measurements, but these tasks are impossible due to the danger of such a situation. However, in many capsizing accidents, a close connection with rolling motion was found. Accordingly, the rolling motion of a fishing boat, which is the core of a fishing vessel capsizing alarm system, has been accurately measured and a time domain based on a rolling motion simulation has been performed. This information was used to verify the algorithm for a capsizing alarm system. Firstly, the characteristics of rolling motion were measured through a motion experiment. For small vessels such as fishing vessels, it was difficult to interpret viscosity due to analytical methods including CFD and potential codes. Therefore, an experiment was carried out focusing on rolling motion and a rolling mode RAO was derived.

• Journal of Korea Multimedia Society
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• v.6 no.7
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• pp.1189-1199
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• 2003

This paper presents a new method for the motion detection of vehicles using hierarchical motion estimation and parallel processing. It captures the road image by using a CMOS sensor. It divides the captured image into small blocks and detects the motion of each block by using a block-matching method which is based on a hierarchical motion estimation and parallel processing for the real-time processing. The parallelism is achieved by using tile pipeline and the data flow technique. The proposed method has been implemented by using an embedded system. The proposed block matching algorithm has been implemented on PLDs(Programmable Logic Device) and clustering algorithm has been implemented by ARM processor. Experimental results show that the proposed system detects the motion of vehicles in real-time.

• The KIPS Transactions:PartB
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• v.10B no.7
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• pp.811-814
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• 2003

In this paper, we propose a fast block-matching motion estimation method using the cross pattern and the hexagonal pattern. For the block-matching motion estimation method, full search finds the best motion estimation, but it requires huge search time because it has to check every search point within the search window. The proposed method makes use of the fact that most of motion vectors lie near the center of block. The proposed method first uses the cross pattern to search near the center of block, and then uses the hexagonal pattern to search larger motion vectors. Experimental results show that our method is better than recently proposed search algorithms in terms of mean-square error performance and required search time.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.7
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• pp.495-505
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• 2009

A two-dimensional circular cylinder freely falling in a channel has been simulated by using immersed boundary - lattice Boltzmann method (IB-LBM) in order to analyze the characteristics of motion originated by the interaction between the fluid flow and the cylinder. The wide range of the solid/fluid density ratio has been considered to identify the effect of the solid/fluid density ratio on the motion characteristics such as the falling time, the transverse force and the trajectory in the streamwise and transverse directions. In addition, the effect of the gap between the cylinder and the wall on the motion of a two-dimensional freely falling circular cylinder has been revealed by taking into account a various range of the gap size. As the cylinder is close to the wall at the initial dropping position, vortex shedding in the wake occurs early since the shear flow formed in the spacing between the cylinder and the wall drives flow instabilities from the initial stage of freely falling. In order to consider the characteristics of transverse motion of the cylinder in the initial stage of freely falling, quantitative information about the cylinder motion variables such as the transverse force, trajectory and settling time has been investigate.

• Korean Journal of Applied Biomechanics
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• v.13 no.1
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• pp.39-50
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• 2003

The purpose of this experiment was to find out the stages of result of specific character for Horse Vaulting Yeo motion To put the Yeo movement in process, we needed a gymnastics athlete C height of 165cm, weight of 62kg, age of 32, personal history of 21 years, and tested the athlete 5 times of motion training, and picked out the 2 best motion and analyzed it. Athletic reason is vertical motion, time uses, horizontal motion, distance, speed, and analyzed many other reasons as a result, and finally ended up with this conclusion. 1. After the take off on the board horizontal speed gradually decreased However, reverse of that, it showed that vertical speed increased. 2. While contacting the Horse Vaulting, horizontal speed decreased and vertical speed kept on increasing. Taking off Com the Horse Vaulting, horizontal, showing short time of training, 3m vertical height is shown after using Yeo motion at the peak of second fly jump. 3. While contacting the Horse Vaulting, both arms were showing the flection shape Especially this is also while contacting the Horse Vaulting, left arm was showing $90^{\circ}$ angle, and this has happened between the process of transition period of fast horizontal speed to vertical speed. 4. While contacting the Horse Vaulting, perfect blocking of the left arm must be complete for the right arm to have the perfect blocking as well.

• Journal of Navigation and Port Research
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• v.48 no.2
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• pp.116-124
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• 2024

Automatic docking of small planing ship is a critical aspect of maritime operations, requiring accurate prediction of motion states to ensure safe and efficient maneuvers. This study investigates the use of Artificial Neural Network (ANN) to predict motion state of a small planing ship to enhance navigation automation in port environments. To achieve this, simulation tests were conducted to control a small planing ship while docking at various heading angles in calm water and in waves. Comprehensive analysis of the ANN-based predictive model was conducted by training and validation using data from various docking situations to improve its ability to accurately capture motion characteristics of a small planing ship. The trained ANN model was used to predict the motion state of the small planning ship based on any initial motion state. Results showed that the small planing ship could dock smoothly in both calm water and waves conditions, confirming the accuracy and reliability of the proposed method for prediction. Moreover, the ANN-based prediction model can adjust the dynamic model of the small planing ship to adapt in real-time and enhance the robustness of an automatic positioning system. This study contributes to the ongoing development of automated navigation systems and facilitates safer and more efficient maritime transport operations.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.3
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• pp.77-88
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• 1995

It is assumed in the block matching algorithm(BMA) that all the pels in a block have a same motion vector. Then, the motion vector of a block in the BMA is matched to only one or none of the objects in the worst case if objects in a block have different motion vectors. This is apparent in the motion estimation using the fast BMA which has the effect of reducing the computation time and hardware complexity, compared to the full search BMA. Although the motion vector in the motion estimation using small block size is accurate, the increased number of bits is required to represent motion vectors. In this paper, new motion vector segmentation with less additional information and hardware complexity than the conventional method is proposed. In the proposed method, a motion vector is derived from the block for motion vector segmentation and another motion vector is extracted from four neighboring blocks to consiture a motion vector pair. For the accurate motion vector of each subblock, the motion vector is assigned to each subblock by mean squared error measure. And the overlapped motion compensation using window is also applied to reduce displaced frame difference.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.639-642
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• 2005

Motion Estimation(ME) is an important part of video compression, because it requires a large amount of computation. Half-pixel and quarter-pixel motion estimation allows high video compression rates but it also has high computation complexity. In this paper we suggest a new and efficient motion estimation algorithm for half-pixel and quarter-pixel motion estimation using SAD values. In the method, an integer-pixel motion vector is found and then only three neighboring points of the integer-pixel motion vector is evaluated to find the half-pixel motion vector. The quarter-pixel motion vector is also found by using a similar method. Experimental results of our method shows 20% reduction in computation time, when compared with those of a conventional method, while producing same quality motion vectors.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.4 no.3
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• pp.58-66
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• 1995

It is very important to test motion accuracy and performance of NC machine tools as they affect that of all other machines machined by them in industry. In this paper, in has become possible to detect errors of linear displacement of radial direction for circular motion test using newly assembled magnetic type of linear scales so called Magnescale ball bar system, and to calculate time interval getting error motion data and revolution angle of circular motion in machining center using tick pulses come out from computer. And a set of error data gotten from test is expressed to a plot by computer treatment and to numerics of error motion by statistical treatment and results of test are compared with those of Renishaw ball bar system.

• International Journal of Advanced Culture Technology
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• v.9 no.3
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• pp.367-372
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• 2021

The purpose of this study is to suggest that the movement expression activity of intellectually disabled people is effective in the learning process of LMA motion recognition based on Kinect sensor. We performed an ICT motion recognition games for intellectually disabled based on movement learning of LMA. The characteristics of the movement through Laban's LMA include the change of time in which movement occurs through the human body that recognizes space and the tension or relaxation of emotion expression. The design and implementation of the motion recognition model will be described, and the possibility of using the proposed motion recognition model is verified through a simple experiment. As a result of the experiment, 24 movement expression activities conducted through 10 learning sessions of 5 participants showed a concordance rate of 53.4% or more of the total average. Learning motion games that appear in response to changes in motion had a good effect on positive learning emotions. As a result of study, learning motion games that appear in response to changes in motion had a good effect on positive learning emotions