• The Journal of Korean Academy of Prosthodontics
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• v.46 no.2
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• pp.209-216
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• 2008

Statement of problem: It is difficult about assessing the loosening tendency of conical connection type implant after cyclic loading with diamond like carbon coating one-piece abutments, and also about the retightening effect. Purpose: This study was performed to investigate the influence of one-piece abutment screw retightening after $5.0{\times}10^{4}$ cyclic loading and Diamond like coating Material and methods: Thirty two ITI implant were divided to 4 groups. Group 1,3-titanium abutment, group 2,4 - diamond like carbon coated abutment. Group 1,2 - $20.0{\times}10^{4}$ cyclic loading after $5.0{\times}10^{4}$ cyclic loading, Group 3,4- after $20.0{\times}10^{4}$ Cyclic loading. After cyclic loading, periotest values were taken and removal torque values of abutments were measured with a digital torque gauge. Results: 1. The removal torque of group 2 after $5.0{\times}10^{4}$ cyclic loading is slightly greater than the other groups but not significantly higher than others (P>0.05). 2. The final removal torque values after $20.0{\times}10^{4}$ cyclic loading of group 1 is bigger than group 3, and group 2 is bigger than group 4, but not significantly higher (P>0.05). 3. The final removal torque values after $20.0{\times}10^{4}$ cyclic loading of all groups are not significantly different (P>0.05).

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.4
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• pp.370-378
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• 2016

Purpose: The purpose of this study was to investigate screw joint stability and sagittal fit between internal connection implant fixtures of two different manufacturers and customized abutments. Materials and methods: Internal connection implant systems from two different manufacturers (Biomet 3i system, Astra Tech system) were selected for this study (n=24 for each implant system, total n=48). For 3i implant system, half of the implants were connected with Ti ready-made abutments and the other half implants were connected with Ti CAD-CAM custom ones of domestic-make (Myplant, Raphabio Co., Seoul, Korea) and were classified into Group 1 and Group 2 respectively. Astra implants were divided into Group 3 and Group 4 in the same way. Micro-CT sagittal imaging was performed for fit analysis of interfaces and preloading reverse torque values (RTV) were measured. Results: In the contact length of fixture-abutment interface, there were no significant differences not only between Group 1 and Group 2 but also between Group 3 and Group 4 (Mann-Whitney test, P>.05). However, Group 2 and Group 4 showed higher contact length significantly than Group 1 and Group 3 in abutment-screw interface as well as fixture-screw one (Mann-Whitney test, P<.05). In addition, RTV was lower in CAD-CAM custom abutments compared to ready-made ones (Student t-test, P<.05). Conclusion: It is considered that domestically manufactured CAD-CAM custom abutments have similar fit at the fixture abutment interface and it could be used clinically. However, RTV of CAD-CAM custom abutments should be improved for the increase of clinical application.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.219.1-219.1
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• 2014

전자소자 산업의 미세화 및 대형화에 따라 플라즈마 밀도, 전위, 온도, 균일도 등 과 같은 플라즈마 특성을 제어하는 것은 차세대 플라즈마 장치 개발에 있어 매우 중요한 요소라고 할 수 있다. 특히, 급격한 소자의 미세화에 따라 플라즈마 공정을 통해 발생할 수 있는 damage는 큰 issue가 되어 왔고, 많은 연구자들은 이를 해결하기 위해서 다각적인 노력을 진행해 왔다. 그중 높은 전자 온도는 높은 전자 에너지에 의해 공정 중 소자를 손상 시키는 주된 원인이라고 보고되고 있으며, 이에 대한 제어기술은 매우 중요하다고 할 수 있다. 본 연구에서는 서로 다른 두 개의 내/외측으로 나뉘어진 나선형 모양의 ICP 안테나를 이용 하여 연구를 진행하였다. 내측의 안테나에는 2 MHz를 연결 하였으며, 외측의 안테나에는 13.56 MHz를 연결 하였으며, 내/외측 안테나에 각각 pulse mode로 입력전력을 인가해 줌으로써 플라즈마의 특성을 관찰하였다. Pulse / CW (Continuous Wave) mode에 있어서 전자온도의 측정을 위해 emissive probe 를 이용하여 plasma potential과 floating potential을 측정하였으며, 이를 통하여 전자온도를 계산하여 구할 수 있었다. Duty ratio 및 pulsing frequency의 변화에 따른 전자온도의 변화를 확인 할 수 있었으며, 그에 따른 플라즈마 균일도를 ion saturation current를 측정함으로써 관찰할 수 있었다. 실제 식각 공정에 있어서 Pulsing 조건에 따른 식각 특성을 관찰하기 위해, SiO2, ACL (Amorphous Carbon Layer)에 대해 식각을 진행하였으며, 식각 메커니즘 분석을 위해 이온에너지 분포의 변화를 PSM (Plasma Sampling Mass-spectroscopy)을 이용하여 측정하였다.

• The Korean Journal of Zoology
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• v.35 no.4
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• pp.414-427
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• 1992

Octopus variabilis의 흡반을 광학현미경과 주사전자현미경 그리고 투과전자현미경을 이용하여 그 미세구조를 관찰하였기에 이에 보고하는 바이다. 또한 내측상피 부위 돌기구 조물 속에서 관찰된 세포들은 핵을 둘러싼 세포들이 공포화 현상으로 인하여 해면처럼 보였다. 이 세포들은 감각과 수축에 관여하는 해면질성인 세포로 생각된다. 외측 상피조직에서는 2종의 분비성인 감각세포(A 및 B형세포)차 2종의 상피성인 감각세포(C 및 D형세포)가 관찰되었다. 분비성인 감각세포는 감각이외에 점액분비 기능을 소지하였으며, 상피성인 감각세포는 상피의 지지와 감각기능을 수행하는 것으로 생각되었다. 흠반을 구성하고 있는 근섬유는 중앙이 기린 도나스 형태로서 10-15개의 종선이 나타났다. 또한 부위에 따라서는 근섬유들은 서로 집결하여 원주형의 근육 기등을 형성하기도 했는데 이들은 신경섬유에 의하여 서로 연결 되고 통제되었다.

• 한국방재학회:학술대회논문집
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• 2010.02a
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• pp.96.2-96.2
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• 2010

본류부에서 지류부로 유입되는 흐름의 내측 벽면에는 토사나 오염물의 퇴적물침전이 발생하게 된다. 이는 개수로 분류흐름의 특성으로 인하여 이차류 흐름이 나타나는 분리구역이 발생하기 때문이다. 수치모의를 실행하여 Hsu 등(2002)과 Ramamurthy 등 (2007)의 분류흐름 수로의 결과값과 수치모의를 통한 결과를 비교하여 신뢰성이 높음을 알 수 있었다. 본 연구에서는, 분류흐름에서 발생하는 분리구역을 줄이기 위해 분류가 시작되는 본류의 수로의 크기 조절을 통하여 분리구역의 크기를 줄였다. 또한 변형으론 인한 분리구역을 줄이기 위해 본류와 지류가 만나는 모서리 지점을 곡선과 대각선으로 연결하여 유수흐름을 완만하게 만든 지형들을 제안하였다.

• Korean Journal of Applied Biomechanics
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• v.18 no.3
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• pp.51-59
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• 2008

The objective of this study is to kinematically analyze forehand & backhand strokes of abscission handicap wheelchair table tennis athletes. The participant of this study were picked out of national athletes who have abscission handicap. Forehand stroke movement was expected to show a throw like motion. However, external rotation and internal rotation of the right arm created a backswing and an impact. Backhand stroke was expected to show a push like motion, and as expected, proximal part of the body didn't participate in the stroke motion, but the distal part, the right arm, rotated internally to backswing and external rotated to impact to form a push like motion. Forehand swing was expected to show throw like motion according to the Link Segmental System principle. However, abscission handicap athlete didn't show clear linking structure connecting proximal and distal parts. Successful strokes were dependant only on the angle of arm rotation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.5
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• pp.601-608
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• 2019

In this study, the effect of hull appendages on the high-speed catamarans with reverse bow shapes is compared and analyzed by numerical analysis and circulating water tank model test. The reverse bow shape showed an improved wave shape by shifting the generation position of forward divergent wave to the stern direction and was effective in resistance and stable running posture (Kim et al., 2019). In the model test results of the running performance as the wave patterns and the change of the running posture due to the fin fitted with the inner side of the inverted bow and the interceptor, 1) Trim characteristics of the inverted bow 2) Improvement of superposition of inner wave by Fin 3) The trim control by the fin and the interceptor is considered to be effective in reducing the impact of the two hull connection decks (wetdeck).

• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.77-85
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• 2003

The lifting and lowering supports method makes up for the weak points in the classical method and provides makes construction economical effect to construction. The application of pre-compression to continuous steel box girder bridges makes it possible to reduce the amount of steel, the height of girders and consequently, the cost consequentlyof the bridges' construction by through the process of concrete filling- up and the lifting-lowering of the inner supports. The lifting and lowering supports method is apt to cause local buckling in the lower flange and web plates by due to the process of the lifting of the inner supports. Therefore iln this study, therefore, the possibility of local buckling could be decreased, in consideration of the lifting force and the buckling strength of stiffened plates, by increasing the number of longitudinal stiffeners and the installation of extended longitudinal stiffeners on the lower flange and the web plates in the range of positive moment.

• Korean Journal of Veterinary Research
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• v.16 no.2
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• pp.205-219
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• 1976

한국재래산양(韓國在來山羊) 12마리의 후지근(後肢筋)을 절개하여 관찰하였던 바 다음과 같은 결과를 얻었다. 1. 한국재래산양(韓國在來山羊)의 후지근(後肢筋)에서는 다음과 같은 근(筋)들을 관찰할 수 있었다 : 소요근(小腰筋) M. psoas minor, 대요근(大腰筋) M. psoas major, 장골근(腸骨筋) M. iliacus, 요방형근(腰方形筋) M. quadratus lumborum, 대퇴근막장근(大腿筋膜張筋) M. tensor fasciae lata, 중둔근(中臀筋) M. gluteus medius, 심둔근(深臀筋) M. gluteus profundus, 둔이두근(臀二頭筋) M. gluteobiceps, 반건양근(半腱樣筋) M. semitendinosus, 반막양근(半膜樣筋) M. semimbranosus, 봉공근(縫工筋) M. sartorius, 박근(薄筋) M. gracilis, 치골근(恥骨筋) M. pectineus, 내전근(內轉筋) M. adductor, 대퇴방형근(大腿方形筋) M. quadratus femoris, 외폐쇄근(外閉鎖筋) M. obturatorius externus, 내폐쇄근(內閉鎖筋) M. obturatorius internus, 쌍자근(雙子筋) M. gemelli, 대퇴사두근(大腿四頭筋) M. quadriceps femoris, 제삼비골근 M. fibularis tertius, 내측지신근(內側趾伸筋) M. extensor digitorum medialis, 장지신근(長趾伸筋) M. extensor digitorum longus, 전경골근(前脛骨筋) M. tibialis cranialis, 장비골근 M. fibularis longes, 외측지신근(外側趾伸筋) M. extensor digitorum lateralis, 비복근 M. gastrocnemius, 가제미근(筋) M. soleus, 천지굴근(淺趾屈筋) M. flexor digitorum superficialis, 심지굴근(深趾屈筋) M. flexor digitorum profundus, 슬와근(膝窩筋) M. popliteus, 골간근(骨間筋) M. interosseus medius. 2. 천둔근(淺臀筋)의 전부(前部)는 대퇴근막장근(大腿筋膜張筋)과 융합된 것 같고, 후부(後部)는 대퇴이두근(大腿二頭筋)과 융합된 것 같다. 그러나 천둔근(淺臀筋)의 후부(後部)와 대퇴이두근(大腿二頭筋)이 결합된 것으로 생각되는 부분에는 완전융합이 일어나지 않고 천둔근(淺臀筋)을 구분(區分)할 수 있을 정도로 표면으로 2근(筋)을 분리(分離)할 수 있었다. 3. 외측지신근(外側趾伸筋)과 내측지신근(內側趾伸筋)의 건(腱)은 부전골의 원위(遠位) 1/3부(部)에서 서로 건막성(腱膜性)띠에 의하여 서로 연결 되었는데, 이 건막성(腱膜性) 띠는 건섬유(腱纖維)의 방향(方向)으로 보아 외측지신근(外側趾伸筋)의 건(腱)에서 분리(分離)되어 나온 한 가지 (branch)가 내측지신근(內側趾伸筋)의 건(腱)으로 이행되고 있었다. 4, 양(羊)에서 볼 수 있는 이상근(梨狀筋) M. piriformis과 장모지신근(長母趾伸筋) M. extensor hallucis longus은 나타나지 않았다.

• Water for future
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• v.21 no.4
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• pp.399-406
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• 1988

Presented in this paper is a brief summary of the basic theory and observation from a laboratory investigation aimed at determining flow characteristics and ice jam topography in a sinuous channel, and in a single-bend channel. The sinuous channel comprised thirteen $90^{\circ}$ bends and was of comparatively small s\aspect ratio. The single-bend channel was a $180^{\circ}$ bend, which was an order of magnitude large in width as well as aspect ratios than the sinuous channel. The simulated ices were polyethylene and polypropylene beads and block. The streamwise velocities near the bottom were larger than that of surface in sinuous channel and forming ice jam in sinuous channel, this phenoumena were found strongly. Jams were generally thicker along the inner bank of bends. The path of maximum-streamwise velocity was displaced towards approachs side of the inner bank of bends. Radial variation of jam thickness was to be regular by increasing size of ice fragments. The rate of jam head progression around outer bank of the single bend was faster than that of inner bank and its velocity was roughly steady. With increasing Froude number, jm thickness became less uniformly distributed; being generally thicker along the inner bank and near the jam's toe. Two-layer model might be adaptable for the computing the streamwise velocity in shallow river bends. Two cells of secondary flow cound be expected in ice covered-river bends.