• Journal of applied mathematics & informatics
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• v.27 no.3_4
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• pp.581-589
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• 2009

In this paper, we are concerned with a class of nonlinear second-order differential equations with a nonlinear damping term and forcing term: $$(r(t)k_1(x(t),x'(t)))'+p(t)k_2(x(t),x'(t))x'(t)+q(t)f(x(t))=0$$. Passage to more general class of equations allows us to remove a restrictive condition usually imposed on the nonlinearity. And, as a consequence, our results apply to wider classes of nonlinear differential equations. Some illustrative examples are considered.

• International journal of advanced smart convergence
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• v.7 no.2
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• pp.1-6
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• 2018

In this paper, we propose an automatic left ventricle segmentation method in computed tomography angiography (CTA) using separating energy function. First, we smooth the images by applying anisotropic diffusion filter to remove noise. Secondly, the volume of interest (VOI) is detected by using k-means clustering. Thirdly, we divide the left and right heart with split energy function. Finally, we extract only left ventricle from left and right heart with optimizing cost function including orientation term.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.5
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• pp.561-568
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• 2003

Surface ozone concentrations are highly sensitive to meteorological variability. Therefore, in order to reveal the long-term changes in ozone due to the changes in precursor emissions, we need to remove the effects of meteorological fluctuations on the annual distribution of surface ozone. In this paper, the meteorologically adjusted trends of daily maximum surface ozone concentrations in two major Korean cities (Seoul and Busan) are investigated based on ozone data from 11 (Seoul) and 6 (Busan) sites over the period 1992 ∼ 2000. The original time series consisting of the logarithm of daily maximum ozone concentrations are splitted into long-term, seasonal and short-term component using Kolmogorov-Zurbenko (KZ) filter. Meteorological effects are removed from filtered ozone series using multiple linear regression based on meteorologcial variables. The long-term evolution of ozone forming capability due to changes in precursor emission can be obtained applying the KZ filter to the residuals of the regression. The results indicated that meteorologically adjusted long-term daily maximum ozone concentrations had a significant upward trend (Seoul: ＋ 3.02% yr$^{-1}$ , Busan: ＋ 3.45% yr$^{-1}$ ). These changes of meteorologically adjusted ozone concentrations represent the effects of changing background ozone concentrations as well as the more localized changes in emissions.

• Restorative Dentistry and Endodontics
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• v.47 no.1
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• pp.11.1-11.11
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• 2022

This study aimed to describe the outcomes of the GentleWave system (GW) (Sonendo) on root canal treatment. Published articles were collected from scientific databases (MEDLINE/PubMed platform, Web of Science, Scopus, Science Direct and Embase). A total of 24 studies were collected from August/2014 to July/2021, 20 in vitro and 4 clinical. GW System was not associated with extrusion of the irrigant, promoted faster organic dissolution than conventional syringe irrigation (CSI), passive ultrasonic irrigation (PUI) continuous ultrasonic irrigation (CUI) and EndoVac, reduced more bacterial DNA and biofilm than PUI and CUI, promoted higher penetration of sodium hypochlorite into dentinal tubules than PUI and CUI in vitro, and removed more intracanal medication than CSI and PUI. GW was able to remove pulp tissue and calcifications. Moreover, its ability to remove hard-tissue debris and smear layer was better than that of CSI, and its ability to remove root canal obturation residues was lower or similar to that of PUI, and similar to that of CSI and EndoVac. Regarding root canal obturation of minimally instrumented molar canals, GW was associated with high-quality obturation. Clinically, the success rate of endodontic treatment using GW was 97.3%, and the short-term postoperative pain in the GW group was not different from CSI. Further research, mainly clinical, is needed to establish whether GW has any advantages over other available irrigation methods.

• Journal of Chest Surgery
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• v.27 no.6
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• pp.502-505
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• 1994

Neurogenic tumors of the mediastinum may have an intraspinal component connected by a narrowed segment of tumor in the intervertebral foramen,hence the descriptive term dumbbell.Recently we had an occasion to remove a dumbbell neurilemmoma in a 62 years old woman using an approach designed to allow wide posterolateral thoracotomy and concomitant laminectomy for a single stage removal of the entire tumor. The mass in the posterior mediastinum was discovered on routine chest roentgenography. CT scan demonstrated a dumbbell shaped soft tissue mass density compressing spinal canal but preserving spinal cord. There were no neurologic signs. A standard posterolateral thoracotomy incision was made to remove tumor mass and then T5 unilateral laminectomy has done by Neurosurgeon. 7 x 7 cm sized extrapleural neurilemmoma was round, cystic, soft mass which covered parietal pleural with invaded regional vertebrae. There was no postoperative neurological complication.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.3
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• pp.544-556
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• 1997

All ceramic restorations except In-Ceram Alumina system gave a good esthetics and an exellent marginal fidelity. The flexural strength of them had about 150MPa, so the indication is only single crown. By using In-ceram Alumina System(450Mpa), it is thought to be possible to construct bridge for its high flexural strength. But the prognosis is unclear, The purposes of this study are to clear short term prognosis of In-Ceram bridge restorations, to elucidate its clinical significance. Among 22 In-Ceram Bridge restored in our department, 11 In-Ceram bridges with follow up were used. The period of placement is from 1 to 18 months. The results were as follows : 1. Among follow up 11 bridges, 2 bridges were fractured. One is 4 unit in maxillary lateral incisors, the other is 3 unit bridge in maxillary canine and premolar. Including 11 bridge without follow up, failure rate is very low(2/22). 2. The fracture sites are connector areas between abutment and pontic. To maintain In-Ceram bridge for long term period, it is needed to remove the nonphysiologic occlusal force and to have sufficient thickness of alumina core. For estabilishing clinical use of In-Ceram bridges, it is thought to need clinical research during long term period.

• Journal of KIISE:Software and Applications
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• v.37 no.8
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• pp.629-640
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• 2010

The exemplar-based inpainting model is widely used to remove objects from natural images and to restore a damaged region. This paper presents a method which improves the performance of the conventional exemplar-based inpainting model by modifying three major parts in the model: data term, confidence term and patch selection. While the conventional data term is calculated using the local gradient, the proposed method uses 16 compass masks to get the global gradient to make the method robust to noise. To overcome the problem that the confidence term gets negligible in the inside of the eliminated region, a method is proposed which makes the confidence term decrease slowly in the eliminated region. The patch selection procedure is modified so that the closer patch has higher weight. Experiments showed that the proposed method produced more natural images and lower reconstruction error than the conventional exemplar-based inpainting.

• Journal of Animal Science and Technology
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• v.65 no.1
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• pp.149-159
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• 2023

The purpose of this study was to evaluate the effects of castration method and short-term fattening periods on Hanwoo cattle. Thirty-two Hanwoo calves (average body weight: 148.4 ± 19.8 kg) were used. The calves were randomly assigned in a 2 × 2 factor according to two castration methods (castration or hemi-castration) and two short-term finishing periods (24 months or 26 months). The final body weight increased significantly as the fattening period increased (p < 0.05), and the average daily weight gain was higher in the hemi-castration groups than in the castration groups (p < 0.05). After surgical castration, testosterone concentration was higher in the hemi-castration group than in the castration group during the entire experimental period (p < 0.05). The rib eye area was wider in the hemi-castration group than in the castration group (p < 0.01).An interaction effect was observed between the castration method and short-term fattening period (p < 0.05). Marbling and auction price scores differed between castration methods and were higher in the castration group than in the hemi-castration group (p < 0.01). Gross receipts and net income increased in the castration group compared to the hemi-castration group (p < 0.01) and showed a tendency to increase with the short-term fattening period, but there was no significant difference. Thus, castration to remove both testicles is essential for economic profit through producing high-quality Korean beef meat, and short-term fattening for 26 months, rather than 24 months, can benefit more by increasing carcass weight and meat quality.

• Proceedings of the Optical Society of Korea Conference
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• 2006.02a
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• pp.335-336
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• 2006

We propose a method of encryption and decryption of binary data using 2-step phase-shifting digital interferometry. This technique reduces the number of interferograms in the phase-shifting interferometry. The binary data has been expressed with random code and random phase. We remove the dc-term of the phase-shifting digital interferogram to restore the original binary data. Simulation results shows that the proposed technique can be used for binary data encryption and decryption.

• Journal of KIEE
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• v.10 no.1
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• pp.23-27
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• 2000

The relative degree one and weakly minimum-phase conditions have been major obstacles for passification of the given system. In this paper, a dynamic output feedback passifier which can remove the obstacles is presented. The proposed method does not require any modification of the given output except just adding a new term. Therefore, the scheme is more suitable for output feedback passification.