• Journal of Broadcast Engineering
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• v.2 no.2
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• pp.216-224
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• 1997

In this paper, we propose a depth information extraction method for intermediate image synthesis. As stereo matching method, MBS(Multiple-Baseline Stereo) method has been proposed, in which the matching accuracy increases by using the multiple camera, but there are some inherent problems such as computational complexity, boundary overreach(BO) in depth map, and occlusion. So, we propose the modified version of MBS so called Multi-Resolution MBS(MR-MBS). Moreover, we also propose an adaptive occlusion area processing technique to improve the accuracy of the depth information in occlusion area.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.11
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• pp.5624-5638
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• 2016

A novel method based on Surf points is proposed to detect and lock-track single ground target in aerial videos. Videos captured by moving cameras contain complex motions, which bring difficulty in moving object detection. Our approach contains three parts: moving target template detection, search area estimation and target tracking. Global motion estimation and compensation are first made by grids-sampling Surf points selecting and matching. And then, the single ground target is detected by joint spatial-temporal information processing. The temporal process is made by calculating difference between compensated reference and current image and the spatial process is implementing morphological operations and adaptive binarization. The second part improves KALMAN filter with surf points scale information to predict target position and search area adaptively. Lastly, the local Surf points of target template are matched in this search region to realize target tracking. The long-term tracking is updated following target scaling, occlusion and large deformation. Experimental results show that the algorithm can correctly detect small moving target in dynamic scenes with complex motions. It is robust to vehicle dithering and target scale changing, rotation, especially partial occlusion or temporal complete occlusion. Comparing with traditional algorithms, our method enables real time operation, processing $520{\times}390$ frames at around 15fps.

• Journal of Biomedical Engineering Research
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• v.24 no.5
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• pp.421-425
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• 2003

In this study the occlusion of dural-sac. the outer membrane of spinal cord in the lumbar region. was quantitatively analyzed using one motion segment finite element model. Occlusion was quantified by calculating cross sectional area change of dural-sac for different compressive impact duration (loading rate) due to bony fragment at the posterior wall of the cortical shell in vertebral body. Dural-sac was occluded most highly in the range of 8∼12 msec impact duration by the bony fragment intruding into the spinal canal. $\Delta$t = 400 msec case 4 % cross sectional area change was calculated. which is the same as the cross sectional area change under 6 kN of static compressive loading.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.215-215
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• 1996

The present study examined chronic effects of transient focal cerebral ischemia on the substantia nigra, a remote exofocal area, using immunohistochenmical and receptor autoradiographic techniques. Transient focal cerebral ischemia was induced by middle cerebral artery (MCA) occlusion for 60 or 90 min followed by reperfusion using silicone-coated 4-0 nylon monofilament in male Wistar rats. After 1- or 2-week reperfusion following transient MCA occlusion, there were partial losses of tyrosine hydroxylase-immunoreactive dopaminergic neurons, incieases in glial fibrillary acidic protein-immunoreactive cells (gliosis), decreases in [$^3$H]YM-09151-2 binding for dopamine D$_2$ receptors, and marked atrophy in the ipsilateral substantia nigra. The precise mechanism(s) of exofocal damage to the substantia nigra is remained to be elucidated.

• Journal of International Society for Simulation Surgery
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• v.3 no.2
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• pp.46-48
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• 2016

Purpose In face reocognition area, estimating occlusion in face images is on the rise. In this paper, we propose a new face recognition algorithm based on dual sparse representation to solve this problem. Method Each face image is partitioned into several pieces and sparse representation is implemented in each part. Then, some parts that have large sparse concentration index are combined and sparse representation is performed one more time. Each test sample is classified by using the final sparse coefficient where correlation between the test sample and training sample is applied. Results The recognition rate of the proposed algorithm is higher than that of the basic sparse representation classification. Conclusion The proposed method can be applied in real life which needs to identify someone exactly whether the person disguises his face or not.

• Journal of TMJ Balancing Medicine
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• v.2 no.1
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• pp.13-16
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• 2012

Objectives: The quadrant theorem is a theorem proposed by C. M. Guzay in the field of functional, holistic dentistry. There are not much of scientific literature on the quadrant theorem. This study briefly reviewed basic concepts of quadrant theorem. Methods: A publication by Guzay and research articles were searched and reviewed. The quadrant theorem is depicted as a series of illustrations and accompanied explanations. Results: The primary concept of the quadrant theorem was presented in 1952. Based on geometric biophysics of the occlusion and related anatomical functions, physiological pivotal axis of the mandible is analyzed to occurs at the dens (the sub-atlas area). Composite muscular activity links the mandibular posture with C1-C2, which is then linked with the spinal posture. Twenty illustrations are progressively presented on the physiognomy, occlusion, and analysis of anatomical functions. The balanced distribution of the forces gives the durability of the functions in life. Conclusions: The quadrant theorem provides a functional linkage between the mandibular posture and the upper cervical vertebrae.

• Journal of Korea Multimedia Society
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• v.12 no.12
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• pp.1745-1754
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• 2009

PTZ (Pan-Tilt-Zoom) camera based surveillance systems are enlarging their field of application due to their wide observable area. We aimed to detect both static and moving objects in automated working space by using a PTZ camera. For object detection we used background difference method because of the high quality segmentation. However, the method has a problem called 'hole' that is caused by non-continuous surveillance of the PTZ camera and its own characteristics. Moreover, the occlusion which occurs when the moving object overlaps with the static object should be solved for robust object detection. In this paper, we suggest a region-based technique for updating background images thereby overcoming the hole and occlusion problem. Through experiments with real scenes, it was verified that meaningful static and/or moving objects were detected very well.

• Journal of IKEEE
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• v.28 no.1
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• pp.65-71
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• 2024

This paper proposes a neural network that can reduce the number of parameters while reducing matching errors in occluded regions to increase the accuracy of depth maps in stereo matching. Stereo matching-based object recognition is utilized in many fields to more accurately recognize situations using images. When there are many objects in a complex image, an occluded area is generated due to overlap between objects and occlusion by background, thereby lowering the accuracy of the depth map. To solve this problem, existing research methods that create context information and combine it with the cost volume or RoIselect in the occluded area increase the complexity of neural networks, making it difficult to learn and expensive to implement. In this paper, we create a depthwise seperable neural network that enhances regional feature extraction before cost volume generation, reducing the number of parameters and proposing a neural network that is robust to occlusion errors. Compared to PSMNet, the proposed neural network reduced the number of parameters by 30%, improving 5.3% in color error and 3.6% in test loss.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.73-79
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• 2000

This study investigated whether propofol, an intravenous, non-barbiturate anesthetic, could reduce brain damage following global forebrain ischemia. Transient global ischemia was induced in gerbils by occlusion of bilateral carotid arteries for 3 min. Propofol (50 mg/kg) was administered intraperitoneally 30 min before, immediately after, and at 1 h, 2 h, 6 h after occlusion. Thereafter, propofol was administered twice daily for three days. Treated animals were processed in parallel with ischemic animals receiving 10% intralipid as a vehicle or with sham-operated controls. In histologic findings, counts of viable neurons were made in the pyramidal cell layer of the hippocampal CA1 area 4 days after ischemia. The number of viable neurons in the pyramidal cell layer of CA1 area was similar in animals treated with a vehicle or a subanesthetic dose of propofol. In terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) assay, semiquantitative analysis of dark-brown neuronal cells was made in the hippocampal CA1 area. There was no significant difference in the degree of TUNEL staining in the hippocampal CA1 area between vehicle-treated and propofol-treated animals. These results show that subanesthetic dose of propofol does not reduce delayed neuronal cell death following transient global ischemia in Mongolian gerbils.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.3
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• pp.198-203
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• 2012

Excessive occlusal wear results in unacceptable damage to the occluding surfaces, and can cause pulpal injury, occlusal disharmony, impaired function, and aesthetic deformity. Patients with severely worn dentition need to be classified as several categories relative to the vertical dimension of occlusion (VDO) and the interocclusal distance for the prosthetic space. When treating patients classified as those who have excessive wear without loss of occlusal vertical dimension but with limited space, we could consider treating them at an increased vertical dimension of occlusion. Treatments at an increased vertical dimension of occlusion may provide stability, given that the amount of its increase was minimal, and a perfected occlusion was achieved after enough stabilization period. A 50-year-old male visited the department of Prosthodontics in Yonsei University Dental Hospital with the chief complaint of worn teeth on lower anterior area. Reconstruction at an increased vertical dimension of occlusion was planned. After the compatibility of the new vertical dimension of occlusion had been confirmed under interim fixed restorations, definitive fixed restorations composed of full-contour monolithic zirconia prostheses were placed. This case presents that a satisfactory clinical result was achieved by restoring the worn dentition at an increased vertical dimension of occlusion with an improvement in esthetics and function.