• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.50.2-50.2
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• 2019

Understanding three-dimensional structure and parameters (e.g., radial velocity, angular width, source location and density) of coronal mass ejections (CMEs) is essential for space weather forecast. In this study, we determine CME mean density in solar corona and near the Earth. We select 38 halo CMEs, which have the corresponding interplanetary CMEs (ICMEs), by SOHO/LASCO from 2000 to 2014. To estimate a CME volume, we assume that a CME structure is a full ice-cream cone which is a symmetrical circular cone combined with a hemisphere. We derive CME mean density as a function of radial height, which are approximately fitted to power-law functions. The average of power-law indexes is about 2.1 in the LASCO C3 field of view. We also obtain power-law functions for both CME mean density at 21 solar radii and ICME mean density at 1AU, with the average power-law index of 2.6. We estimate a ratio of CME density to background density based on the Leblanc et al.(1998) at 21 solar radii. Interestingly, the average of the ratios is 4.0, which is the same as a default value used in the WSA-ENLIL model.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.119-121
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• 2022

In this paper, we will make a model that finds optimal phase for each crossroad. When the traffic volume, traffic capacity, and the lane width of every direction is given for each crossroad, we aim to find the most efficient phase. We established an evaluation function that evaluates the efficiency of each phase using the values of the average waiting time in one direction, the average delay time, the standard deviation of the delay time, and the average delay time in each direction. The time allocation to optimize a phase pattern can be obtained by using the gradient decent method. Through this research, we hope to decrease the waiting time in transporation, thus improving the overall traffic condition in cities.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.1
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• pp.16-24
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• 2022

A computational study of combined thermal and solutal convection (double diffusive convection) in a sealed crystal growth reactor is presented, based on a two-dimensional numerical analysis of the nonlinear and strongly coupled partial differential equations and their associated boundary conditions. The average Nusselt numbers for the source regions are greater than those at the crystal regions for 9.73 × 10³ ≤ Gr_t ≤ 6.22 × 10⁵. The average Nusselt numbers for the source regions varies linearly and increases directly with the thermal Grashof number form 9.73 × 10³ ≤ Gr_t ≤ 6.22 × 10⁵ for aspect ratio, Ar (transport length-to-width) = 1 and 2. Additionally, the average Nusselt numbers for the crystal regions at Ar = 1 are much greater than those at Ar = 2. Also, the occurrence of one unicellular flow structure is caused by both the thermal and solutal convection, which is inherent during the physical vapor transport of Hg₂Br₂. When the aspect ratio of the enclosure increases, the fluid movement is hindered and results in the decrease of thermal buoyancy force.

• Journal of Periodontal and Implant Science
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• v.28 no.4
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• pp.785-797
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• 1998

This study has been done to prove that keratinized gingiva is required for the periodontal health and to analyse the adequate width that is necessary. Until now, the study on frenum has been documented on changing its location. But the location or the formation of the frenum has not been reported. This experiment has used 173 patients from the department of periodontology of Dankook University to investigate the width of keratinized gingiva, the formation of the frenum and its location for the frequency. This study also looks into the relationship between the gingival recession and the structure of the frenum, and affects they have on periodontal health. The width of the keratinized gingiva in the mandible has been found to be highest in the lateral incisor than in the central incisor. The width decreased from the canine to the first premolar until it reached the molar. The interproximal area of the mandibular frenum was 77.9%, which was greater than the frequency (22.1%) from the midline of the teeth. The highest frequency of frenum was at 30.6% in between the both central incisor then second greatest at 20.6% in between the right canine and the right first premolar. Frenum was not found in between the second premolar and the distal area. In the morphology of the frenum, it was found that 43.4% out of 551 parts were found to be a single narrow frenum, and the double or triple ligamented form of the complex frenum were found in similar frequency of 237 parts, but the broad frenum was rarely frequent. The incisal area was popular mostly with the single narrow frenum, the left premolar area frequented 57.4%, and the right premolar frequented 64.7%. Because the distance between the frenum apex and the gingival margin measured to be about 5mm or greater, the frenum apex started in the mucogingival junction and not just below the keratinized gingiva. In the 551 area investigated, 48.3% of gingiva showed recession, incisal area had recession the least at 44.9%, right buccal side at 47.4%, and right buccal side frequented the highest at 52.1%. The teeth that showed recession recessed at the average of 2.151.0.mm and the left canine showed the greatest amount of gingival recession. In the investigation to find out if the keratinized gingiva and the gingiva recession had mutually related somehow, the width of keratinized gingiva showed no affect on the probing depth, but had affected in the gingiva recession. This investigation showed that the gingival recession and the morphology of the frenum related in that, the single narrow frenum had recessed the least and the broad frenum recessed the most. With this analysis, a conclusion was drawn that the morphology of the frenum had affected in the gingical recession.

• Archives of Plastic Surgery
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• v.38 no.2
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• pp.173-181
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• 2011

Purpose: Masseter muscle is an important muscle of mastication. Because it has a great influence on the shape of low facial contour, patients who have masseteric hypertrophy show square-shaped jaw appearance. As aesthetic procedures for the reduction of the masseter muscle volume, radiofrequency ablation or botulinum toxin injection is at the center of attention. Authors studied the anatomical measurement of the thickness and width of masseter muscle and the surface mapping of the maximal thickness point using computed tomography (CT) scan to identify the useful guide for the injection of botulinum toxin in masseteric hypertrophy patients. Methods: We analyzed 2 mm-thickness OMU (ostiomeatal unit) CT of 112 normal people (224 masseter muscles) taken from June 2009 to May 2010. First, we measured the thickness, width and depth of the masseter muscle from the skin surface and analysed each by side, sex and age, respectively. The distribution of the thickness of the muscle and the correlation of thickness and width of the muscle were studied also. Second, we underwent surface mapping of the maximal thickness point using CT analysis by means of checking the vertical and horizontal distance from the angle of the mandible. Results: The average thickness and width of the masseter muscle was 17.73 mm and 40.78 mm in the male patients and were 14.33 mm and 37.42 mm in the female patients. Statistically, both figures of the male patients were larger than those of the female patients. However, the depth of the muscle from the skin surface in female patients (7.37 mm) was larger than that of the male patients (6.15 mm). There were no statistical difference in side or age. The width and thickness of the masseter muscle were in the positive correlation. The location of maximal thickness point of the masseter muscle was 27.77 mm vertically and 27.68 mm horizontally in the male patients, and 25.19 mm vertically and 25.42 mm horizontally in the female patients from the angle of mandible. Conclusion: We were able to present statistical evidence of the diagnosis and treatment of the masseteric hypertrophy regarding the anatomical measurements such as the thickness and width. And the maximal thickness point of the masseter muscle may be a useful guide for the clinical procedures of botulinum toxin injection.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.13 no.3
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• pp.96-106
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• 2014

Necessarily traffic policies have been biased in car than pedestrian, so pedestrian's environment is getting worse. Result of this situation our accident rate is high as 36.4%, compared to OECD member countries with average rate of 17.8%(in 2009). Increasing interest for pedestrians environment improvement, and it make an effort to build environment to guarantee walk and safety of pedestrians. Analysis on the binary logistic regression(BLR) was used. The dependent variable is occurring from the road width of less than 9m accident, and independent variable extracted can be obtained from the traffic accident data. Traffic accident on roads having width of less than 9 meters affecting variables is when the driver is straight, when the driver is female, when the pedestrian is walk driveway, and so on. To prevent it, efforts is demanded to protect handicapped, to build safe pedestrians environment using C-ITS and to decrease speed of going straight vehicle on roads having width of less than 9 meters.

• The Journal of Sustainable Design and Educational Environment Research
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• v.19 no.4
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• pp.60-69
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• 2020

This research is a preliminary study to find out the module of 20 students in a classroom. This research investigated the widths of passages in the 30 classrooms of 5 elementary schools in Namyangju City, Korea. The conclusions were as follows: First, the area of unit for 1 student was 650 (W) × 950 (D). Second, the desk placements for most classrooms were one-way types (87%), and group-study types constituted 13%. Third, the width between the blackboard and the very front desk was 2.17 m. The width of passage between the very back seat and the backside lockers was 1.32 m. The width of passage between the sidewall and the nearby desk was 0.8 m. The width of passage between the window and the nearby desk was 0.8 m. The average widths of 2 vertical passages between the desks were respectively 0.67 m and 0.68 m. Fourth, the area of the teacher was 2.1-2.25 m × 2.16 m = 4.5-4.8 ㎡.

• Journal of Periodontal and Implant Science
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• v.23 no.1
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• pp.183-192
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• 1993

The purpose of this epidermiological analysis was to evaluate the periodontal status of Korean young adults(twenties) in order to provide detail & baseline data for frequence of periodontal disease. Two hundred and fifty young adults, aged 20-29 years, were selected by random sampling. Dental visity, scaling treatment, education, income, toothbrushing frequence & method were checked, and plaque index(Loe and silness), calculus index(Ramfjord), gingival index(Loe and silness), attached gingival width, perio probing depth, gingival recession were measured. The obtained results were as follows. 1. Average plaque index(1.96), calculus index(1.43), gingival index(1.7) were higher in mandible than maxillar. It was most prevalent in lst molar. 2. Average attached gingival width(4.0mm) was wider in maxillar than mandible. It was most prominent in lateral incisor. 3. Pocket depth(>4mm) was distributed in 42% subject, it was higher in mandible than maxilla and most prevalent in 1st molar. 4. Gingival recession(>1mm) was distributed in 94% subject, it was higher in mandible than maxilla, and most prevalant in canine. 5. According to unpaired t-test, palque index, calculus index, gingival index were not statistically significant in history of scaling treatment, level of eduction and account of income, but were showed statistically significant in histrory of dental clinic.(PB0.05) 6. According to ANOVA test, correlation between tooth-brushing(frequence, method) and gingival index was showed statistically significant.(P<0.05) 7. There was gingival recessionof 87% subject in only one time brushing, 80% subject in two time, and 68% subject in three times. There was gingival recessionof 68% subject in leftright direction tooth brushing, 73% subject in upper-low method and 77% subject in combination method.

• Journal of Periodontal and Implant Science
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• v.38 no.4
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• pp.717-722
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• 2008

Purpose: The subepithelial connective tissue graft(SCTG) has been proven to be a highly predictable treatment modality for coverage of gingival recession. This case report was performed to evaluate the effect of various root coverage procedures using SCTG on gingival recession. Materials and Methods: Three patients presents with Miller's class I recession defect on the maxillary canine. Each other SCTG(coronally advanced flap, Bruno's Tech., envelope Tech.) were performed for root coverage. Clinical parameters assessed included recession depth, recession width, and keratinized gingival width. Measurements were taken at baseline and 2 months and follow up end. Results: The average of root coverage was 4 mm(100% of the pre-operative recession depth) at the 2, 5 months examination. The average increase of keratinized tissue between the baseline and the 2 months amounted to 3.2mm. Conclusion: Within the above results, various root coverage using SCTG is an effective procedure to Miller's class I recession defect and patient could be satisfied aesthetic requirement.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.7
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• pp.980-987
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• 2012

In order to investigate the effect of physical forms of starter diets on performance, weaning age, nutrient digestibility and rumen biochemical factors, 24 female of neonatal Brown Swiss calves (average body weight of $39.5{\pm}1.2kg$) were randomly assigned to three treatments. Dietary treatments were mashed (MS), pelleted (PS), and texturized (TS) starter using 8 calves from birth till 90 days of age in each treatment. Diets were formulated to be iso-nitrogenous with 21% crude protein. Based on the experimental results, calves that received PS and TS diets, had significant higher average daily gain (ADG) than those receiving MS (p<0.01). Dry matter intake in calves fed PS and TS was greater than calves fed MS (p<0.05), but there was no significant difference in feed efficiency. Treatments had no effect on initiation of rumination. Weaning age of calves in MS was longer than the other two treatments (p<0.05). Crude protein and organic matter digestibility in MS treated calves were lower than other treatments (p<0.05). No differences were observed in neutral detergent fiber (NDF) and ash digestibility among treatments (p>0.05). Ruminal pH was higher (p<0.01) in MS than the other groups, but ruminal ammonia (g/dl) concentration was not different among the treatments. Body measurements such as body length, pin width, hip width, pin to hip length, size of metacarpus and metatarsus bones, hip height, wither height, stomach size and heart girth were not significantly different among the treatments. Overall, it is concluded that starter diets in the form of pellet and texture can improve performance in neonatal Brown Swiss calves compared to the mashed form.