• The korean journal of orthodontics
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• v.25 no.3 s.50
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• pp.263-271
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• 1995

The purpose of this study nab to evlauate and compare the effect of the variable factors of wire on the elastic properties of looped rectangular wire. Five variable factors were presented-material(Hi-T, blue Elgiloy), wire size(.016'$\;\times\;$.022', .018'$\;\times\;$.025'), loop length(15mm, 20mm), loop configuration(open loop, closed loop), gabling (non-gable, gable). So, the total 256 specimens were divided into 32 groups, and each of those nab pulled on Instron testing machine. The load-deflection curve of each wire obtained, from which force, range in elastic limit, and stiffness were computed and analyzed statistically. The results were obtained as follows : 1. All of the variable factors - wire material, size, loop length loop configuration, and gabling - took a significant effect on load-deflection rate of looped wire. 2. The force at elastic limit was the smallest in the group of Hi-T, .016'$\;\times\;$.022', 20mm loop length, open loop, non-gable, and the largest in the group of blue Elgiloy, .018'$\;\times\;$.025', 15mm loop length, closed loop, non-gable. 3. The range at elastic limit was the smallest in the group of Hi-T, .018'$\;\times\;$.025', 15mm loop length, open loop, non-gable, and the largest in the group of HI-T, .016'$\;\times\;$.022', 20mm loop length, closed loop, gable. 4. Loop configuration and loop length were the most effective factors on the elastic properties of looped wires, and gabling was the least effective.

• Neonatal Medicine
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• v.15 no.2
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• pp.166-171
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• 2008

Purpose : This study was performed to determine the rate of neonatal symptomatic spontaneous pneumothorax, and the corresponding clinical characteristics, co-morbidities, and outcomes. Methods : The demographic characteristics, clinical symptoms and signs, associated abnormalities, methods of treatment, and outcomes were investigated in 22 neonates with symptomatic spontaneous pneumothorax in the neonatal intensive care unit (NICU) of Chonnam University Hospital between March 2003 and February 2008. Results : The rate of spontaneous pneumothorax was 0.55%. Among the 22 neonates, the number of outborns was 15 (68.2%) and the number of males was 12 (54.5%). The main symptoms and signs were chest retraction, tachypnea, and cyanosis. The pneumothoraces were more frequent on the right side (59.1%) and all cases were diagnosed within 3 days of life. Four cases (18.2%) had urologic abnormalities and 7 cases (31.8%) had cranial abnormalities by ultrasonography. The treatments included oxygen (81.8%) and oxygen with chest tube drainage (18.2%). All of the infants survived and the overall outcomes were favorable. Conclusion : When respiratory symptoms and signs are develop abruptly in otherwise healthy newborns, the clinician should suspect a spontaneous pneumothorax and check a chest x-ray as soon as possible. Although the outcome of neonatal symptomatic spontaneous pneumothorax is favorable, renal and cranial ultrasonography are needed because of the higher possibility of urologic abnormalities and germinal matrix/intraventricular hemorrhage than in newborns without a pneumothorax.

• The korean journal of orthodontics
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• v.23 no.2 s.41
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• pp.217-227
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• 1993

Preadjusted appliance, following the original concept of the Andrews Straight-Wire appliance, became increasingly common in the 1980s. In six phases of treatment, anchorage control, leveling and aligning, overbite control, overjet reduction, space closure, and finishing are very effective with using the preadjusted appliances. Space closure is the phase of treatment in which the difference between standard edgewise and preadjusted mechanics is most noticeable. Orthodontists have been able to reduce the use of closing loops and, because of the level slot lineup, enjoy the advantages of sliding mechanics. In 1990, Dr. John C. Bennett and Richard P. McLaughlin introduced the new space closure system, namely, elastic 'tiebacks'. They found an $.019'\times.025'$ working archwire most effective in an .022'-slot system. Hooks of .024' stainless steel or .028' brass wire are soldered to the upper and lower archwires. The force required for space closure is delivered by elastic 'tiebacks'. An elastic modulo stretched by 2-3mm(to twice its normal length) usually delivers 0.5-1.5mm of space closure per month. Group movement and sliding mechanics are combined for gentle, controlled space closure, so that about 0.5mm of incisor retraction and 0.5mm of mesial molar movement can be seen each month. The tiebacks are replaced every four to six weeks. By using the elastic 'tiebacks', the next two cases were treated during space closure. Even though we found some clinical problems of this mechanics, long treatment time, hard to control of vertical dimension and anchorage, the application method of this system is so simple that orthodontists can manage many patients during short chair time. But we must apply this mechanics after perfect understanding of the biomechanics in tooth movement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.328-334
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• 2020

At the recent practice test of the Remote Controlled Munition system (for practice), nine out of 125 samples were generated. Although 7.2 % misfires occurred, the acceptance test met the defense standards. Minimizing the probability of broken fuses is essential to reducing the number of samples and improving the AQL according to the process quality. In addition, it is necessary to increase military training and ensure user safety. In the case of practical grenades, hit-type detonators are applied. Unlike the normal design, which takes a hit by strikers, a different design of a hit by pressure from a pressure generator was used. This study analyzed the detonator surface through computational fluid dynamics. The results showed that the probability of functional weakness and retraction increased with increasing slope of the detonator surface. To overcome this, design changes were made to improve the fuse crimping process and increase the detonator holder seat. A performance test with the same number of samples from the whole quantity was operated. The probability of broken fuses was 0 %. Therefore, the reliability and performance of the ammunition can be improved and is expected to contribute to the drawing and process design when developing similar ammunition.

• Journal of KIISE
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• v.43 no.10
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• pp.1115-1123
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• 2016

Assumption-based truth maintenance system (ATMS) is a tool that maintains the reasoning process of inference engine. It also supports non-monotonic reasoning based on dependency-directed backtracking. Bookkeeping all the reasoning processes allows it to quickly check and retract beliefs and efficiently provide solutions for problems with large search space. However, the amount of data has been exponentially grown recently, making it impossible to use a single machine for solving large-scale problems. The maintaining process for solving such problems can lead to high computation cost due to large memory overhead. To overcome this drawback, this paper presents an approach towards incrementally maintaining the reasoning process of inference engine on cluster using Spark. It maintains data dependencies such as assumption, label, environment and justification on a cluster of machines in parallel and efficiently updates changes in a large amount of inferred datasets. We deployed the proposed ATMS on a cluster with 5 machines, conducted OWL/RDFS reasoning over University benchmark data (LUBM) and evaluated our system in terms of its performance and functionalities such as assertion, explanation and retraction. In our experiments, the proposed system performed the operations in a reasonably short period of time for over 80GB inferred LUBM2000 dataset.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1998.11a
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• pp.25-29
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• 1998

본 논문은 얼굴 인식 또는 표정 인식 분야에 있어서 중요한 특징을 나타내는 얼굴과 얼굴의 주요소인 눈과 입, 눈썹의 영역 추출 및 그의 윤곽선·추출에 관한 방법을 제시한다. 얼굴요소의 영역 추출은 엣지 정보와 이진화 영상을 병합하여 이용한 프로젝션 분석을 통하여 얼굴 및 각 얼굴요소를 포함하는 최소포함사각형(MER: Minimum Enclosing Rectangle)을 추출하였다. 얼굴 영상에 관련된 윤곽선 연구에는 가변 템플릿(Deformable Template), 스네이크(Snakes: Active Contour Model)를 이용하는 연구들이 이루어지고 있는데 가변 템플릿 방법은 수행시간이 느리고 추출된 윤곽선의 모양이 획일 된 모양을 갖는 특성이 있다. 본 논문에서는 사람마다 얼굴요소의 모양의 개인차가 반영되고 빠른 수렴을 할 수 있는 스네이크 모델을 정의하여 눈, 입, 눈썹, 얼굴의 윤곽선 추출 실험을 하였다. 또한 스네이크는 초기 윤곽선의 설정이 윤곽선의 추출 곁과에 큰 영향을 미치므로, 초기 윤곽선의 설정 과정이 매우 중요하다. 본 논문에서는 얼굴 및 각 얼굴요소를 포함하는 각각의 최소 포함 사각형(MER)을 추출하고, 이 추출된 MER 내에서 얼굴 및 각 얼굴요소의 일반적인 모양을 초기 윤곽선으로 설정하는 방법을 사용하였다. 실험결과 눈, 입, 얼굴의 MER의 추출은 모두 성공하였고, 눈썹이 흐린 사람들의 경우에만 눈썹의 MER추출이 졸지 않았다. 추출된 MER을 기반으로 하여 스네이크 모델을 적용한 결과, 눈, 입, 눈썹, 얼굴의 다양한 모양을 반영한 윤곽선 추출 결과를 보였다. 특히 눈의 경우는 1차 유도 엣지 연산자에 의한 엣지 와 2차 유도 연산자를 이용한 영점 교차점(Zero Crossing)과 병합한 에너지 함수를 설정하여 보다 더 나은 윤곽선 추출 결과를 보였다. 얼굴의 윤곽선의 경우도 엣지 값과 명도 값을 병합한 에너지 함수에 의해 비교적 정확한 결과를 얻을 수 있었다.잘 동작하였다.되는 데이타를 입력한후 마우스로 원하는 작업의 메뉴를 선택하면 된다. 방법을 타액과 혈청내 testosterone 농도 측정에 응용하여 RIA의 결과와 비교하여 본 바 상관관계가 타액에서 r=0.969, 혈청에서 r=0.990으로 두 결과가 잘 일치하였다. 본 실험에서 측정된 한국인 여성의 타액내 testosterone농도는 107.7$\pm$12.0 pmol／l이었고, 남성의 타액내 농도는 274.2$\pm$22.1 pmol／l이었다. 이상의 결과로 보아 본 연구에서 정립된 EIA 방법은 RIA를 대신하여 소규모의 실험실에서도 활용할 수 있을 것으로 사려된다.또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다. 더욱이, 조선의 ${\ulcorner}$구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to look into the origin of the letter designs in the Chinese character culture

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.188-193
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• 2010

Purpose: The purpose of this study was to evaluate the clinical and radiological results of a modified Phemister method reinforcing the 4 strands of an Ethibond sling for acromioclavicular joint dislocation. Materials and Methods: Between September 1999 and May 2007, 30 acromioclavicular joint dislocation cases underwent a modified Phemister method reinforcing the 4 strands of an Ethibond sling. The average follow-up period was 28.2 months (range: 24~33 months). Clinical outcomes were evaluated using the Weitzman classification; the state of coracoclavicular space reduction was done using radiologic findings. Results: According to the Weitzman classification, there were 24 excellent, 4 good and 2 fair case outcomes. The average coracoclavicular distance improved from 16.9 mm to 7.3 mm immediately after surgery. The average ratio of coracoclavicular distance comparing to the contralateral side at the final follow-up was 1.24 (range: 0.68~1.71). Complications included retraction of K-wires in 5 cases and restriction of joint motion in 4 cases. Conclusion: The modified Phemister operation using augmentation of the coracoclavicular ligament by 4 strands of Ethibond is an effective treatment modality in acromioclavicular joint dislocation.

• Pediatric Infection and Vaccine
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• v.9 no.2
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• pp.201-207
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• 2002

Purpose : We analyzed clinical features and causal viruses of acute lower respiratory tract infections(LRTIs) in order to improve the management of these infections. Methods : From end of April to early May 2001, amongst 30 children at a local institute for children's adoption and welfare, 13 were admitted to the hospital with the diagnostic impression of acute LRTIs. Nasopharyngeal aspirates were sent in Seoul National University Hospital for viral culture of respiratory syncytial virus(RSV), adenovirus, parainfluenza virus. Results : One or more viral agents were identified in 4 cases(30.7%) : were RSV(15.4%), adenovirus(7.7%), and a mix of these two viruses(7.7%). Initial symptoms were fever(69%), cough(100%), tachypnea(54%), chest retraction(69%), rale(85%) and wheezing(15%). Leukocytosis was noted in 23%, CRP increased more than 10 mg/L in 46%. Chest X-ray abnormalities were 69%. Conclusion : Although viruses were identified in 30.7%, further studies should be made for prevention and treatment of acute viral LRTIs.

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.179-204
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• 1998

The purpose of this research was to investigate the efficacy of Goiwhasan extract powder on the gastric injuries, antiulcer, gastrointestinal tract and blood hemostasis. Animals were used through this studies mice and rats. All animals were divided into 3 groups, contol group(no treatment), sample Ⅰ group(375mg/kg administration), sample Ⅱ group(750mg/kg administration). The gastric injuries and ulcer have been made by using pyloric ligation, indomethacin, HCI-ethanol, acetic acid and then The histological observation was followed. In the gastrointestinal tract, gastric juice secretion, gastric acidity, pepsin output, blood gastrin and secretin level, transport potentials in the small and large intestine were checked. And studies on blood hemostasis were performed on normal hemostatic activities and plasma prothrombin time, plasma recalcification time, plasma fibrinogen levels in the hypoprothrombinemic mice induced by warfarin. The results were as follows: 1. The antigastric ulcer effects on the pyloric ligation, indomethacin, HCl-ethanol, acetic acid induced gastric injuries were shown in Sample Ⅱ group(p<0.05). 2. Through the morphologic examination on the acetic acid induced ulcer, Sample Ⅰ group showed mild regeneration of epithelium and slight decrease of periulcer edema then that of Control group, while Sample Ⅱ group showed more retraction of round ulcer site, remarkable loss of swelling and edema then that of Control group, and revealing the regenerated epithelium in the surrounding ulcer site. Thus it was noted that both Sample groups have antigastriculcer effects on the experimentally induced gastric ulcer. 3. The inhibitory effects on gastric juice were noted in both Sample Ⅰ group(p<0.05) and Sample Ⅱ group(p<0.01). However, only Sample Ⅱ group showed the inhibitory effects on total acidity and pepsin output(p<0.05). 4. The significant inhibition of blood gastrin level showed at 30 min.(P<0.05) and 90 min.(P<0.05) after starting medication in only Sample Ⅱ group, but significance of blood secretin level in both groups was not recognized. 5. Any significant changes in barium sulfate transport in the small intestine of mice was not recognized in both groups, but the significantly inhibitory effect in large intestine was recognized in both Sample Ⅰ group(p<0.05) and Sample Ⅱ group(p<0.001). 6. In hemostatic effect on both normal mice and hypoprothrombinemic mice induced by warfarin, the significantly shortening effect on coagulation time was seen in only Sample Ⅱ group(p<0.01). 7. On plasma prothrombin time in hypoprothrombinemic rat induced by warfarin, Sample Ⅱ group have shortened the prothrombin time significantly(p<0.001). 8. On plasma reclcification time in hypoprothrombinemic rat induced by warfarin, the recalcification time have been shortened significantly in both Sample Ⅰ group(p<0.05) and Sample Ⅱ group(p<0.01). 9. On plasma fibrinogen levels in hypoprothrombinemic rat induced by warfarin, the fibrinogen contents in Sample Ⅱ have been decreased significantly(p<0.01). Overall the above results suggest that Goiwhasan has an therapeutic efficacy on antigastric ulcer and blood hemostasis. Further studies would be needed on the interaction of its herbal medicine and its mechanism in the future.

• The Journal of Korean Medicine
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• v.29 no.5
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• pp.29-40
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• 2008

Objectives : It has been reported that Sophorae Subprostratae Radix (SSR) has a neuroprotective effect on cerebral ischemia in animals. In the present study, the authors investigated the neuroprotective effect of SSR on glutamate excitotoxicity. Glutamate excitotoxicity was induced by using NMDA, AMPA, and KA in PC12 cells and in organotypic hippocampal slice cultures. Methods :Methanolic extract of SSR was added at 0.5, 5, and 50 ${\mu}$g/ml to culture media for 24 hours. The effects of SSR were evaluated by measuring of cell viability, PI-stained neuronal cell death, TUNEL-positive cells, and MAP-2 immunoreactivity. Results : SSR increased PC12 cell viabilities significantly against AMPA-induced excitotoxicity, but not against NMDA-induced or KA-induced excitotoxicity. In organotypic hippocampal slice cultures damaged by NMDA-induced excitotoxicity, SSR attenuated neuronal cell death significantly in the CA1, CA3, and DG hippocampal regions and reduced TUNEL-positive cells significantly in CA1 and DG regions. In organotypic hippocampal slice cultures damaged by AMPA-induced excitotoxicity, SSR attenuated neuronal cell death and reduced TUNEL-positive cell numbers significantly in the CA1 and DG regions. In organotypic hippocampal slice cultures damaged by KA-induced excitotoxicity, SSR attenuated neuronal cell death significantly in CA3, but did not reduce TUNEL-positive cell numbers in CA1, CA3 or DG. In organotypic hippocampal slice cultures damaged by NMDA-induced excitotoxicity, SSR attenuated pyramidal neuron neurite retraction and degeneration in CA1. Conclusions : These results suggest that the neuroprotective effects of SSR are related to antagonistic effects on the NMDA and AMPA receptors of neuronal cells damaged by excitotoxicity and ischemia.