• Journal of Periodontal and Implant Science
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• v.27 no.2
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• pp.347-361
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• 1997

The present study investigates the effects of DFDB graft combined with Calcium sulfate membrane on the periodontal wound healing in dehiscence defects of dogs. Following the initiation of general anesthesia by I.V. administration of 30mg/kg of pentobarbital, first premolar was extracted and full-thickness flap was elevated from the second to the fourth premolar. The portion of premolars coronal to the alveolar crest was removed and mesial and distal roots separated to produce single rooted teeth. Exposed root canals were sealed with Caviton and covered completely with flaps sutured. Following the healing period of 12 weeks, the surgical sites were uncovered and $4{\times}4mm$ dehiscence defects were surgically created. Those defects with DFDB graft combined with Calcium sulfate membrane following root planing, were designated as test sites and those with flap surgery-only were designated as controls. 1. No foreign-body reaction or inflammation were observed in either groups. Calcium sulfate was completely resorbed in the test sites. 2. Significantly greater amounts of new cementum was observed in test sites compared with the controls. Significant amounts of functionally orientated collagens were observed in the test sites. 3. New bone formation was observed in significantly greater amounts in test sites. The results suggest that combined graft of DFDB and calcium sulfate is extremely biocompatible with a potential for new bone and cementum formation, and functional alignment of periodontal ligaments.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.49-55
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• 2001

Bacillus anthracis is a gram-positive spore-forming bacterium that causes the disease anthrax. The anthrax toxin contains three components, including the protective antigen (PA), which binds to eucaryotic cell surface receptors and mediates the transport of toxins into the cell. In this study, the entire 2,294-nucleotide protective antigen gene (pag) was sequenced from 4 of B. anthracis strains to identify potential variation in the toxin and to further our understanding of B. anthracis evolution in Korea. Sequence alignment of the entire PA gene from 30 strains representative of the four B. anthracis diversity groups revealed mutations. The mutation of B. anthracis BAK are located adjacent to a highly antigenic region crossing the junction between PA domains 3 and 4 shown to be critical to LF binding. The different mutational combinations observed in this study give rise to 11 PA genotypes and 4PA phenotypes. Three-dimensional analysis of all the amino acid changes (Ala to Val) observed in BAK indicated that these changes are not only close sequentially but also very close in three-dimensional space to the antigenic region importan tfor LF binding. Phylogenetic (cladistic) analysis of the pag corresponded with previous strain grouping based on chromosomal variation, suggesting that plasmid evolution in B. anthracis has occurred with little or no horizontal transfer between the different strains.

• Journal of the Optical Society of Korea
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• v.13 no.4
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• pp.428-433
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• 2009

A photonic crystal fiber with two large air holes outside the holey cladding region is fabricated to induce an effective long periodic grating (LPG) in the core by an electric arc discharge. We believe that the two large air holes lead to the asymmetric perturbation in the core under the electric arc discharge, thereby introducing the coupling to the first higher-order mode. The transmission characteristics of the PCF with the LPG for the external perturbation such as strain, curvature, and temperature are also investigated. It was found that the shift of resonance peak in the transmission spectrum depends on the bending direction. The curvature of 8.55 $m^{-1}$ results in the center wavelength shifts of 1.8, 4.3, and 11 nm for a vertical, diagonal, and horizontal direction of the curvature to the large air-hole alignment, respectively.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.481-487
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• 2020

In this study, finite element analysis was performed to evaluate the track irregularity of the existing track system on urban transit according to the large-scale excavation work that is constructed adjacent to the serviced line. Based on the numerical analysis, the effect of track irregularity generated during the step-by-step construction process was analytically derived, and the stability in terms of track deformation was evaluated through comparison with related standards. As the results, in the case of track irregularity items evaluated based on the relative displacement difference at a certain distance, such as alignment and vertical irregularity, it occurred most clearly at the location where deformation of the existing structure begins, such as the end point of adjacent excavation work. On the other hand, the overall vertical and horizontal displacement of the track was the largest deformation at the center of the construction section. The vulnerable position of the deformed side of the existing structure due to adjacent excavation is analytically proven that the both of the end point section and the center of the construction can be a vulnerable position in terms of track irregularity.

• Journal of The Korean Society of Integrative Medicine
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• v.9 no.3
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• pp.193-201
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• 2021

Purpose : The purpose of this study was to compare the effect of pelvic exercise on the CVA and spinal curve in adults with forward head posture compared to the group using only neck exercise when pelvic exercise was performed in parallel with conventional neck exercise. Methods : GPS 400 and Formetric were used to identify craniovertebral angle (CVA), thoracic kyphosis, lumbar lordosis, and pelvic torsion and were measured by an experienced research manager. Forward head posture (FHP) was selected for people whose angle between the line connecting the ear ball and the seventh cervical spine and the horizontal line is 50 degrees or less. The 30 selected students were randomly divided into 15 experimental groups and 15 control groups. Mackenzie exercise and sling exercise were performed for neck exercise in both the experimental group and the control group, and pelvic exercise using a Swiss ball was additionally performed in the experimental group. All data collected in this study were analyzed using SPSS statistics 21.0. Cervical vetebral angle (CVA), thoracic kyphosis, lumbar lordosis, and pelvic torsion were compared at 0 weeks, 3 weeks, and 6 weeks for each measurement factor using ANOVA with repeated measures. For the statistical significance test, the significance level of α was set to .05. Results : The changes of pelvic torsion, thoracic kyphosis and CVA due to pelvic exercise using Swiss Ball and neck exercise were changed over time, but lumbar lordosis were not changed. And there were no significant differences among the groups. Conclusion : In conclusion, the pelvic correction exercise is considered to be an effective exercise for correcting the FHP and requires regular pelvic correction exercises. We expect the results to be used in clinical trials.

• The KIPS Transactions:PartB
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• v.15B no.4
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• pp.275-284
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• 2008

With increases in recent security requirements, biometric technology such as fingerprints, faces and iris recognitions have been widely used in many applications including door access control, personal authentication for computers, internet banking, automatic teller machines and border-crossing controls. Finger vein recognition uses the unique patterns of finger veins in order to identify individuals at a high level of accuracy. This paper proposes new device and methods for touchless finger vein recognition. This research presents the following five advantages compared to previous works. First, by using a minimal guiding structure for the finger tip, side and the back of finger, we were able to obtain touchless finger vein images without causing much inconvenience to user. Second, by using a hot mirror, which was slanted at the angle of 45 degrees in front of the camera, we were able to reduce the depth of the capturing device. Consequently, it would be possible to use the device in many applications having size limitations such as mobile phones. Third, we used the holistic texture information of the finger veins based on a LBP (Local Binary Pattern) without needing to extract accurate finger vein regions. By using this method, we were able to reduce the effect of non-uniform illumination including shaded and highly saturated areas. Fourth, we enhanced recognition performance by excluding non-finger vein regions. Fifth, when matching the extracted finger vein code with the enrolled one, by using the bit-shift in both the horizontal and vertical directions, we could reduce the authentic variations caused by the translation and rotation of finger. Experimental results showed that the EER (Equal Error Rate) was 0.07423% and the total processing time was 91.4ms.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.157-165
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• 2011

With respect to the trend of highway traffic accident, highway accident is in decline, whileas, the fatality is on an increasing trend. Thus, many efforts to decrease highway traffic accidents and improve the safety, are required. In particular, in case of highway, the management standard by grade for accident black spot is designated. Thus, investing the effect factors by grade for highway traffic accident is required in detail. Thus, in this study, the factors affecting the traffic accidents among the environmental factors based on the graded data for the accident black spot in the applicable section targeting the Seoul-Pusan Express Highway, were reviewed; accident forecasting model which would analyze the characteristics of the accidents for determining the accident grade, was developed. As a result of establishing a model by using Quantification Theory of Type II, considering the characteristics of the dependent and independent variables based on the geometric structure, 'the fixed variable' among the variables relating to the accident, for the variables influencing over the accident grade, 'the type of vans, a chassis and people', 'the trailers, special vehicles and chassis people' and 'the negligence of watching and cloudy weather' were analyzed as common factors, in case of 'horizontal alignment', 'longitudinal slope' and, 'barricade' respectively.

• Journal of the Korean earth science society
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• v.25 no.6
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• pp.418-427
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• 2004

Recently, urban planning with consideration of urban climate, represented by the concept of urban ventilation lane is widely practiced in many countries. The concept of urban ventilation lane is mainly aimed to improve the thermal comfort within urban area in summer season. It has also the aim to reduce the urban air pollution by natural cold air drainage flows which are to be intensified by a suitable alignment of buildings as well as use zonings based on scientific reasons. In this study, the prevailing wind ventilation lane of a local wind circulation and around Daegu for a typical summer days was investigated by using a numerical simulation. The transport of air pollutants by the local circulation winds was also investigated by using the numerical simulation model, the RAMS (Reasonal Atmospheric Model System).The domain of interest is the vicinity of Daegu metropolitan city (about 900 km2). The horizontal scale of the area is about 30 km. The simulations were conducted under a late spring synoptic condition with weak gradient wind and almost clear sky. From the numerical experiment, the following three conclusions were obtained: (1) The major wind passages of the local circulation wind generated by radiative cooling over the representative mountains of Daegu (Mt. Palgong and Mt. Ap) were found. The winds blow down along the valley axis over the eastern part of Daegu as a gravity flow during nighttime. (2) At the flatland, the winds blow toward the western part of Daegu through the city center. (3) As the results, the air pollutants were transported toward the western part of Daegu by the winds during nighttime.

• Journal of Korean Ophthalmic Optics Society
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• v.3 no.1
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• pp.93-101
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• 1998

The present study was conducted to investigate the structural changes in rat cornes. Sixty eyes from one-day-old uneyed rats, fourty eyes from 10-weeks-old adult rats were used. With the increase of age, the epithelial layer was thickened by the addition of new successive cellular layers. Then, the new-born rat's epithelial cells formed a pentagonal shape, and the quality of decidual cells showed a high electron-density, although the boundary between cells was distinctive. The newly produced cells showed a low electron-density so that there was the distinctive difference between light and darkness. In Bowman's layer, collagen fibrils demonstrate a regularly arranged structure along with the age. In stroma's layer, the density of keratocytes was decreased and thereby progressively flattened during the development. The collagenous layer of the adult rats was more distinctive than that of the new-born rats in a form of vertical and horizontal parallel alignment running vertically and horizontally. Descemet's membrane changed its structure significantly along with the age. It changed the shape from "banded-layer" to "non-banded layer" gradually. The thickness was also increased along with the age. Regardless of developmental stages, the endothelium is usually monolayer. During the developmental process, endothelial cells disappeared, so the density of endothelium was also decreased. The empty spaces were replaced by the expansion of adjacent cells.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.2
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• pp.143-151
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• 2012

Purpose: The present study was conducted to investigate whether there is any difference in the centration of spherical RGP lens on cornea according to corneal types, corneal astigmatism and lens fitting states. Methods: Spherical RGP lens was fitted on 29 eyes of round-typed cornea and 45 eyes of symmetric bowtie-typed cornea with 0.00~2.75 D of corneal astigmatism in alignment, steep or flat. Their lens centrations on cornea were analyzed by taking photographs. Results: The centration of spherical RGP lens in the vertical direction was decentrated to downward direction in all cases, and the degree of decentration was not consistent. The lens centration in horizontal direction was significantly more-decentrated to the temporal meridian as base curve of lens was increased, and the degree of decentration was different according to the corneal type, corneal astigmatism and fitting states. With the same degree of astigmatism, the lens decentration to the temporal meridian was bigger in round-typed cornea than that in symmetirc bowtie-typed cornea. Conclusions: The centration of spherical RGP lens varies depending on lens fitting states, corneal astigmatism, and corneal types. Thus, the consideration of these factors may improve the success rate in RGP lens prescription.