• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.8
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• pp.1373-1379
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• 2006

Moving object extraction is one of key research topics for various video services. In this study, a new moving object extraction algorithm is introduced to extract objects using block motion vectors in video data. To do this, 1) a maximum a posteriori probability and Gibbs random field are used to obtain real block motion vectors,2) a 2-D histogram technique is used to determine a global motion, 3) additionally, a block segmentation is fellowed. In the computer simulation results, the proposed technique shows a good performance.

• Restorative Dentistry and Endodontics
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• v.42 no.1
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• pp.34-38
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• 2017

Objectives: The aim of this study was to evaluate the cyclic fatigue resistance of the ProTaper Universal D1 file (Dentsply Maillefer) under continuous and adaptive motion. Materials and Methods: Forty ProTaper Universal D1 files were included in this study. The cyclic fatigue tests were performed using a dynamic cyclic fatigue testing device, which had an artificial stainless steel canal with a $60^{\circ}$ angle of curvature and a 5 mm radius of curvature. The files were randomly divided into two groups (Group 1, Rotary motion; Group 2, Adaptive motion). The time to failure of the files were recorded in seconds. The number of cycles to failure (NCF) was calculated for each group. The data were statistically analyzed using Student's t-test. The statistical significant level was set at p < 0.05. Results: The cyclic fatigue resistance of the adaptive motion group was significantly higher than the rotary motion group (p < 0.05). Conclusion: Within the limitations of the present study, the 'Adaptive motion' significantly increased the resistance of the ProTaper Universal D1 file to cyclic facture.

• Journal of Broadcast Engineering
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• v.26 no.6
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• pp.680-691
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• 2021

Due to the recent developments of attaining 3D contents by using devices such as 3D scanners, the diversity of the contents being used in AR(Augmented Reality)/VR(Virutal Reality) fields is significantly increasing. There are several ways to represent 3D data, and using point clouds is one of them. A point cloud is a cluster of points, having the advantage of being able to attain actual 3D data with high precision. However, in order to express 3D contents, much more data is required compared to that of 2D images. The size of data needed to represent dynamic 3D point cloud objects that consists of multiple frames is especially big, and that is why an efficient compression technology for this kind of data must be developed. In this paper, a motion estimation and compensation method for dynamic point cloud objects using 3D DCT is proposed. This will lead to switching the 3D video frames into I frames and P frames, which ensures higher compression ratio. Then, we confirm the compression efficiency of the proposed technology by comparing it with the anchor technology, an Intra-frame based compression method, and 2D-DCT based V-PCC.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.1-9
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• 2009

In this paper, we propose the efficient processing technique for unavailable data in hardware implementation of motion estimator in H.264/AVC with parallel processing architecture. Motion estimation processing in the hardware is generally based on pipe-lining, some MV data of neighbor blocks are not available, whereas all MV data are valid in software processing where the data are sequentially processed. In this paper, we solve the problem of data being unavailable in MVp computation. To minimize the quality degradation caused by unavailable MVs, in the proposed method, the unavailable MV of a neighboring block is replaced with an integer pel unit MV, an MVp of neighboring blocks, or an MVcol (MV of co-located block). Comparing to the conventional method [7], our method outperformed maximally 0.832dB and 0.179dB for QCIF and CIF, respectively, in terms of BDPSNR.

• Journal of the Korea Fashion and Costume Design Association
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• v.14 no.2
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• pp.75-87
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• 2012

This study aims at measuring and comparing the joint range of motion(ROM) of the elderly, quantitatively understanding the joint ROM and duration for their dressing and undressing of pants with 3D motion analysis equipment, and thereby providing basic data necessary for the future development of clothes carrying functional designs. The findings are as follows. As for the study method, the 9-item joint ROM measurements were conducted with goniometer, and the questionnaire analyses were carried out for t-test, ANOVA, and regression analysis with spss12.0 program. The 3D motion analyses were handled with 3D Motion Analysis Package Version 3.1 Program. The findings are as follows. First, the ROM was shown to be significantly low, as the arthritis-pain consciousness level was felt higher by the subject than the average one. Seven ROM variables, such as hip flexion, hip adduction, hip internal rotation, hip external rotation, knee flexion, ankle dorsiflexion, and ankle plantar flexion, were shown to significantly affect the discomfort level experienced at the time of dressing or undressing. Second, in the motion of inserting the remaining leg into the pant crotch part(3e), the difference of angles in the hip joint and knee joint was the largest between the women in their 20s and the elderly women with arthritis. Third.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.1031-1034
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• 2007

The interactions between two-dimensional and three-dimensional stimulus configurations on visually induced self-motion perception (vection) were examined. The experiment revealed that there is no 2D-3D interaction, and vection strength is determined solely by the size of the moving background stimulus, which should be a primary factor in inducing vection.

• Journal of Broadcast Engineering
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• v.7 no.3
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• pp.219-228
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• 2002

In this paper, we propose a new method of converting 2D video into 3D stereoscopic video, called stereoscopic conversion. In general, stereoscopic images are produced using the motion informations. However unreliable motion informations obtained especially from block-based motion estimation cause the wrong generation of stereoscopic images. To solve for this problem, we propose a stereoscopic conversion method based upon the utilization of key frame that has the better accuracy of estimated motion informations. As well, as generation scheme of stereoscopic images associated with the motion type of each key frame is proposed. For the performance evaluation of our proposed method, we apply it to five test images and measure the accuracy of key frame-based stereoscopic conversion. Experimental results show that our proposed method has the accuracy more than about 90 percent in terms of the detection ratio of key frames.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.287-290
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• 2002

The block matching algorithm motion estimation is a soft-core for hardwired motion estimation block in MPEG-2, H.261 encoder. This motion estimation has been tested and verified to be valid for implementation of FPGA. Efficiency performance of the synthesized motion estimation was up to 89%, and the average PSNR between the original image and the motion-compensated image is 38dB.

• The KIPS Transactions:PartB
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• v.12B no.2 s.98
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• pp.131-136
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• 2005

Motion Estimation (ME) has been developed to remove redundant data contained in a sequence of image. And ME is an important part of video encoding systems, since it can significantly affect the qualify of an encoded sequences. Generally, ME consists of two stages, the integer pixel motion estimation and the half pixel motion estimation. Many methods have been developed to reduce the computational complexity at the integer pixel motion estimation. However, the studies are needed at the half pixel motion estimation to reduce the complexity. In this paper, a method based on the correlations between integer pixel motion vectors and half pixel motion vectors is proposed for the half pixel motion estimation. The proposed method has less computational complexity than the full half pixel search method (FHSM) that needs the bilinear interpolation of half pixels and examines nine half pixel points to the find the half pixel motion vector. Experimental results show that the speedup improvement of the proposed method over FHSM can be up to $2.5\~80$ times faster and the image quality degradation is about to $0.07\~0.69(dB)$.

• Journal of Internet Computing and Services
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• v.4 no.2
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• pp.31-37
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• 2003

Recently, motion capture has become one of the most promising technologies in animation. Realistic motion data can be captured by recording the movement of a real actor with an optical or magnetic motion capture system. This paper deals with motion editing by a geometric mean filter. Since the captured motion has some noises that cause a jerky motion, it needs a smoothing process to make it natural. A geometric mean filter is proposed to produce natural motions without jerky motions. Experimental results show that the geometric mean filter can effectively remove noises that cause a jerky motion and it can guarantee the most natural motions among various spatial filters. This method could be applied to the various fields such as real time animation, virtual reality applications, 3D applications, and etc.