• Proceedings of the KSR Conference
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• 2008.06a
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• pp.299-304
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• 2008

Catenary and Pantograph are a power supply devices for electric trains and shall be steadily contacted. Rail catenary must be installed precisely and managed for stable train operations. But external factors such as weathers, nature, etc., or aging affect catenary geometry. Changed catenary height causes high voltage spark or instant electric disconnection. Big spark and disconnection damage pantograph shoe and catenary coating and might interrupt rail operations. To prevent a big scale spark or electric disconnection catenary maintenance shall be required with catenary geometry measurement systems. In this paper, we describe the development of catenary height and stagger measurement system. The catenary height and stagger measurement system uses Acuity company's AR4000 Range Finder for distance measurement and AccuRange Line Scanner for degree measurement. This system reports suspicious overhead line sections with excessive height and stagger variance.

• Journal of the Korea Institute of Military Science and Technology
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• v.11 no.4
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• pp.5-12
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• 2008

There are some ways to improve precision of conventional munitions by low-cost method. 2D Course Correction Munition(CCM) is one of those ways, which is a 155mm projectile integrated with 2D Guidance Fuze(GF) instead of conventional fuze. 2D GF can correct the projectile trajectory and minimize range and deflection errors from its aimpoint using canard control. In this paper 2D CCM system concept is introduced and its course correction capability is analyzed using PRODAS.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.17 no.2
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• pp.106-111
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• 2004

Vertigo is a symptom, not a disease. The tenn vertigo refers to the sensation of spinning or whirling that occurs as a result of a disturbance in balance. It's sometimes referred to as a hallucination of motion. The cause of vertigo is very various and generally divided into peripheral and central. A patient presented with severe vertigo, nystagmus and heteophoria. She has taken the BanHaBaekChulChunMa-tang and treated by acupuncture. After 2 days, her symptoms become disappeared and about 1 week, all symptoms except heterophoria were disapperaed. And after 2 weeks, heterophoria was disappeared. In conclusion, we diagnosed her case as vestbular neuronitis by her clinical course, but we also considered her illness as vertebrobasilar insufficiency, TIA etc.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.3
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• pp.181-189
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• 2002

This paper describes the positioning accuracies for single and multiple reference stations at fixed stations in Yosu harbor and Pukyong National University in the south coast of Korea from Jan. to Oct. 2001. Also we observed the change of positioning accuracy during a day and the available range of the DGPS reference station. he results obtained are main summarized as follows; 1. With single DGPS reference station, 2drms and the average positioning .error were 5.6m, 7.3m respectively. Measurement positions indicated an incline toward one way away from the actual position. 2. With multiple DGPS reference stations, 2drms and the average position error were 5.5m, 3.2m for the arithmetic mean, respectively. They were 5.3m, 3.8m for the weighted average, respectively. As far as the separation between the user and the reference station, using multiple reference stations improved position accuracy more than using single reference station. 3. The average positioning error increased between 16: 00 and 22 : 00. The average number of observed satellite and HDOP were 7.1m, 0.49 respectively. 4. Coverage of DGPS reference stations in the south coast of Korea was estimated to be 110nm. Signal strength and signal to noise ratio was not available the DGPS signal below 19㏈, 8㏈ respectively.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.105-117
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• 1997

This investigation examined the effect of lateral shift of mandible from functional occlusal interference on the growth of mandible and the growth pattern of mandible shown after the removal of occlusal interference. The followings were performed with the results below : the changes in mandible and condylar cartilage were studied in the experimental group with upper right, lower left incisors cut for 2 and 4 weeks- an 4-week-old rats and the experimental group which had cut for 4 weeks and suspended for 2 weeks. 1. In the 2-week experimental group, the left mandibular length, condylar length, mandibular height and condylar area seemed smaller than those on the right and the normal group ; the right mandibular length and condylar area were smaller than the normal group. 2. In the 4-week experimental group, left condylar area was smaller than the right, but due to the quick changes in adaptability of left mandible, right and left mandibular lengths were similar. compared with the normal group, however, mandibular length and condylar area still remained small. 3. In the 6-week experimental group, the left and the right appeared similar with the mandibular length remaining still shorter than the normal group. 4. In the sagittal plane, the proliferation of the cartilage layers of the left condylar cartilage of the 2-week group appeared to have general repression compared with the right and the normal group. The right side also showed repressed growth compared with the normal group. In the 4 and 6-week groups, however, it was similar to the normal group. 5. In condylar cartilage volume, no significant difference was noted in the comparisions of left and right of the experimental group, nor in the comparison of the same sides of experimental wand normal groups. Based on the above, in case of contralateral incisal cutting in rats, it was observed that the growth of mandible and condyle of the cutting side was repressed, at the same time, the quick adaptability led to similar changes of growth in left and right mandibles. But judging from the similar phenomena throughout the whole experimental period in the changes of condylar cartilage volume in the experimental, right and left, and normal groups, the general overall growth of condylar cartilage was found unrepressed. It was also recognized that the growth of condylar cartilage can take in various directions.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.154-161
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• 2020

Purpose: To describe the clinical and radiology results of a surgical treatment for clinodactyly due to a longitudinal epiphyseal bracket. Materials and Methods: This study analyzed the records of 11 patients (27 case) with clinodactyly due to a longitudinal epiphyseal bracket who underwent an osteotomy or physiolysis between March 1999 and April 2017. The preoperative range of motion of the proximal and distal interphalangeal joints, the subjective satisfaction of the patient, and the degree of angulation to the ulnar side were examined. The patients were classified into two groups: osteotomy and physiolysis. The results were reviewed retrospectively and compared according to the surgical method. Results: The mean age of the patients who underwent osteotomy was 10.3 years. The average preoperative angle was 25.7° and the average postoperative angle was 13.5° the mean correction rate was 47.4%. The mean age of the patients who underwent physiolysis was 6.0 years the mean preoperative angle was 24.5° and the postoperative angle was 10.7°. The average correction rate was 59.4%. No significant difference in the correction angles was observed between the group who underwent the correction osteotomy and the group who underwent the osteotomy. In each group, the postoperative correction was statistically significant. The range of motion at the last follow-up was not significantly different from the preoperative range of motion. Conclusion: In patients with clinodactyly due to longitudinal epiphyseal bracket, osteotomy or physiolysis may be performed selectively according to age, bone age, and radiological progression. Both surgical methods showed good clinical results and deformity correction.

• The korean journal of orthodontics
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• v.28 no.1 s.66
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• pp.113-122
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• 1998

Stabilization splint therapy Precedes orthodontic intervention to enable the operator to find a 'true' centric(which is stable and comfortable), to test the patient's response to a change in the occlusion, prior to embarking upon a complex course of occlusal therapy : and finally, to see if the centric relation position can be stabilized. For this study, 47 malocclusion Patients enrolled for orthodontic treatment at the Department of Orthodontics, College of Dentistry, Chosun University comprised the malocclusion group, little variation of growth factor by the second molar eruption. They had Cr-Co discrepancy beyond normal range. For each patients the stabilization splint with mutually protected type of occlusal scheme was applied for 3 months. Condylar positions in CR and CO were measured using Penadent articulators, Panadent condylar position indicator(CPI), and transcranial projection before & after stabilization splint therapy. On the basis of this study, the results of this study were as follows 1. In all samples using CPI, there were statistical significances in CR-CO discrepancy(p<0.001) both before 8t after stabilization splint therapy. 2. In Rt and Lt+Rt/2 of superior joint space using transcranial projection, there were statistical significances in CR-CO discrepancy({<0.05) before & after stabilization splint therapy. 3. In supero-inferior components using CPI, there were statistical significances in CR-CO discrepancy(p<0.01) before & after stabilization splint therapy. 4. In all components except Rt using transcranial projection, there were no statistical significances in CR-CO discrepancy(p>0.05) before & after stabilization splint therapy. To sum up, CPI might be more effective than transcranial projection to reveal the changes between CR-CO discrepancies and stabilization splint might be more useful appliance for displaying the vertical changes, than the antero-posterior changes, of condylar position.

• The korean journal of orthodontics
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• v.36 no.3 s.116
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• pp.218-227
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• 2006

Although the submentovertex radiograph and surface EMG are not often used due to the difficulty of interpretation, they are accepted as useful diagnostic and analytic aids for skeletal asymmetry. There have been reports which state that they were also useful for the evaluation of vertical skeletal relations. The purpose of this study was to evaluate the correlations between EMG data, measurements from submentovertex radiographs, facial types and facial asymmetry following examination of 60 asymmetric patients. The radiographic corpus length were greater in the nonaffected sides (p<0.001), gonion to interspinosum axis were greater in the affected sides and the mandibular condyle and gonion were located more anteriorly in the non-affected sides than in the affected sides but not significant (p=0.07). The activity of the anterior temporal muscle in rest position was higher in the affected sides than in the non-affected sides (p<0.01). The activity of the masseter muscle at maximum clenching was found to be nonsignificant but it was higher in the affected sides than in the non-affected sides (p=0.09). There was positive correlation between facial index and the intercondylar axes angle (p<0.01). There was positive correlation between masseter muscle activity in maximum occlusion and facial index in the affected and non-affected sides (p<0.05). The results demonstrate that the submentovertex radiograph and EMG can provide useful information for the evaluation of horizontal and vertical skeletal relations.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.6
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• pp.565-572
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• 2018

Recently, UAVs (Unmanned Aerial Vehicles) or drones have gained popularity for the engineering surveying and mapping because they enable the rapid data acquisition and processing as well as their operation cost is low. The applicable fields become much wider including the topographic monitoring, agriculture, and forestry. It is reported that the high geospatial accuracy is achievable with the drone photogrammetry for many applications. However most studies reported the best achievable mapping results using well-distributed ground control points though some studies investigated the impact of control points on the accuracy. In this study, we focused on the drone mapping of corridors such as roads and pipelines. The distribution and the number of control points along the corridor were diversified for the accuracy assessment. In addition, the effects of the camera self-calibration and the number of the image strips were also studied. The experimental results showed that the biased distribution of ground control points has more negative impact on the accuracy compared to the density of points. The prior camera calibration was favored than the on-the-fly self-calibration that may produce poor positional accuracy for the case of less or biased control points. In addition, increasing the number of strips along the corridor was not helpful to increase the positional accuracy.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.1
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• pp.34-41
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• 2022

Recently, digital technology and computer-aided design/computer-aided manufacturing (CAD/CAM) environment have changed the clinician treatment method in the fabrication of dentures. The denture manufacturing method with CAD/CAM technology simplifies the treatment and laboratory process to reduce the occurrence of errors and provides clinical efficiency and convenience. In this case, complete dentures were fabricated using stereolithography (SLA)-based 3D printing in patient with mandibular deviation. Recording base were produced in a digital model obtained with an intraoral scanner, and after recording a jaw relation in the occlusal rim, a definitive impression was obtained with polyvinyl siloxane impression material. In addition, facial scan data with occlusal rim was obtained so that it can be used as a reference in determination of the occlusal plane and in arrangement of artificial teeth during laboratory work. Artificial teeth were arranged through a CAD program, and a gingival festooning was performed. The definitive dentures were printed by SLA-based 3D printer using a Food and Drug Administration (FDA)-approved liquid photocurable resin. The denture showed adequate retention, support and stability, and results were satisfied functionally and aesthetically.