齒科用非貴金屬合金의 微細組織과 硬度에 미치는 熱處理의 影響

柳相烈,成在鉉 慶北大學校 齒科大學 1985 慶北齒大論文集 Vol.2 No.1

The purpose of this study was to investigate the effect of heat treatment on microstructure and hardness of Ticonium Premium 100 alloy in different temperature and times for heat treatment. The first group was quenched in water after heating at 550, 700, 850, 1000℃ for 15 minutes: and the second group, after heating for 5, 30, 60, 120 minutes at 700℃. The hardness number of each specimen was obtained using the Rockwell hardnees tester, and the microstructure of each specimen was compared by means of photomi crograph taken by metallurgical microscope. The results were as follows: For a 15-minute duration, the higher the temperature of heat treatment, the higher the hardness of the alloy, but the hardness decreased at 1000℃. At 700℃, the longer the time of heat treatment, the higher the hardness, but the hardness decreased after the 60-minute period of heat treatment. Optimal temperature of heat treatment was 700-850℃ and the optimal time was less than 60 minutes. Microstructure of the heat-treated alloy showed dendritic structure similar to equi-axed structure, but appeared coarse at 1000℃. Microstructure of the alloy heat-treated at different times turned out to be similar to that of the alloy heat-treated at different temperatures, but coarse grains appeared at a 120 minute duration.

자연사면 산사태 특성에 관한 사례 연구

유남재,전상현,박남선 江原大學校 産業技術硏究所 2007 産業技術硏究 Vol.27 No.B

This paper is a result of a case study about landslides at Whacheon area in Kangwondo occurred during heavy rainfall in 2006. A-day-accumulative rainfalls from July 12 to July 13 and July 15 to July 16 were 120mm and llOmm respectively. Five sites at which slope failures occurred were visited to figure out main causes of slope failures by investigating characteristics of rainfall, geological forrnation, topography and ground surface exploration around the boundary of the landslides. Based on the site investigation characteristics of landslide with respect to rainfall pattern, geological and topographical condition and pattern of landslide were evaluated.

강원도 토석류 산사태의 특성에 관한 연구

유남재,전상현,박남선 江原大學校 産業技術硏究所 2008 産業技術硏究 Vol.28 No.A

This paper is to investigate the characteristics of debris flow landslides in Gangwon Province through literature review, data collection and analyses and site investigation. As results of data analyses about landslides occurred currently in this province, the landslide in the form of debris flow is found to be 55 %. Therefore major loss and costs are caused by discharge of soil and rock fragments from landslide. From results of analyzing the geometrical characteristics of landslide, length of most of landslide is less than 200 m, their width is in the range of 10 - 40 m, most of them are know to be occurred in lower elevation than 400 m. Slope angle is in the range of 25 - 35 degrees. Compahng the period of rainfall intensity with the time of landslide being occurred, occurrence of landslide is quite related to duration of a heavy rainfall. For measures of controlling water flow discharge and debris flow, considering geological and topographical ground conditions, appropriate selection and building check dam, erosion control dam and ring net is very beneficial for reducing the loss and costs caused by the landslide of debris flow.

준설매립지반의 압밀침하에 대한 쌍곡선 침하예측기법의 적용성 연구

유남재,전상현,전진용 江原大學校 産業技術硏究所 2008 産業技術硏究 Vol.28 No.A

Applicability of hyperbolic settlement prediction method to consolidation settlement in the dredged and reclaimed ground was assessed by analyzing results of centrifuge tests modelling self-weight consolidation of soft marine clay. From literature review about self-weight consolidation of soft marine clays located in southern coast in Korea, constitutive relationships of void ratio - effective stress - permeability and typical self-weight consolidation curves with time were obtained by analyzing centrifuge model experiments. For the condition of surcharge loading, exact solution of consolidation settlement curve obtained by using Terzaghi's consolidation theory was compared with results predicted by the hyperbolic method. It was found to have its own inherent error to predict final consolidation settlement. From results of analyzing the self-weight consolidation with time by using this method, it predicted relatively well in error range of 0.04~18% for the case of showing the linearity in the relationship between T vs T/S in the stage of consolidation degree of 60~90 %. However, it overestimated the final settlement with large errors if those relation curves were nonlinear.

임플란트의 collar design이 변연골과 연조직에 미치는 영향

유현상,강선녀,정창모,윤미정,허중보,전영찬 대한치과보철학회 2012 대한치과보철학회지 Vol.50 No.1

연구 목적: 임플란트 경부가 잘 설계된 경우 양호한 연조직 반응을 통해 변연골을 보존하는데 도움이 된다. 본 실험에서는 연, 경조직 경계부에 가장 가까이 위치하는 임플란트의 collar design이 변연골 변화와 연조직 반응에 미치는 영향을 동물실험을 통해 알아보고자 하였다. 연구 재료 및 방법: 2마리의 건강한 Beagle dog에 임플란트 collar design만 다른 두 종류의 임플란트(Neobiotech Co. Seoul, Korea)를 식립하였다. Collar에 bevel 을 부여한 군(Bevel 군)과 "S"자 형태를 부여한 군(Bioseal 군)으로 나누어 마리 당 7개, 군당 7개, 총 14개의 임플란트를 무작위로 식립한 후 Healing abutment를 즉시 체결하였다. 디지털 표준구내 방사선사진을 이용해 4주 간격으로 총 12주간 근원심 변연골 변화를 관찰하였고, 12주에 희생하여 조직학적 분석을 통해 협설 변연골 흡수 및 임플란트 주변 연조직 반응을 평가하였다. Mann-Whitney test를 통해 동일한 방사선 사진 촬영 시점에서 근원심 변연골 변화량 및 조직계측치를 군 간 비교하였고, Kruskal-Wallis test를 통해 방사선 사진상 근원심 변연골 변화량이 시간에 따른 차이가 있는지 군 내 분석 한 후 Duncan test를 통해 사후 검증하였다(α=.05). 결과: 방사선학적 분석 결과 각 촬영 시점에서 두 군간 근원심 변연골 변화량의 차이를 보이지 않았다(P>.05). 군 내에서 시간에 따른 근원심 변연골의 흡수량을 분석한 결과 Bevel 군에서는 시간에 따른 차이를 보이지 않았으나 (P>.05), Bioseal 군에서는 시간에 따른 차이를 보였으며, 4주및8주와 비교했을 때 12주에서 변연골의 증가를 보였다(P<.05). 조직학적 분석 결과 협설측 변연골 흡수량에서 두 군간 차이를 보이지 않았으나 (P>.05), Bevel 군에 비해 Bioseal 군에서 더 견고한 결합조직부착을 관찰할 수 있었으며, 생물학적 폭경의 값은 두 집단 간 차이를 보이지 않은 반면에 (P>.05), 접합상피부착은 Bevel 군에서 유의하게 길었고, 결합조직부착은 Bioseal 군에서 더 길게 나타났다(P<.05). 결론: Bevel 군에 비해 Bioseal 군에서 결합조직부착은 길게 형성된 반면에 접합상피부착은 더 짧게 나타났으며, 생물학적 폭경과 초기 변연골 흡수에는 차이가 없음을 알 수 있었다. 연조직 반응의 차이가 실제 기능하중 하에서 변연골 변화에 미치는 영향에 대해서 향후 연구가 필요할 것으로 생각된다. PURPOSE. The purpose of this study was to investigate the effects of implant collar design on marginal bone change and soft tissue response by an animal test. MATERIALS AND METHODS. Two types of Implant (Neobiotech Co. Seoul, Korea) that only differs in collar design were planted on two healthy Beagle dogs. The implants were divided into two groups, the first group with a beveled collar (Bevel Group) and the second group with "S" shaped collar (Bioseal group). Standardized intraoral radiographs were used to investigate the mesio-distal change of the marginal bone. Histological analysis was done to evaluate the bucco-lingual marginal bone resorption and the soft tissue response adjacent to the implant. Mann-Whitney test was done to compare the mesio-distal marginal bone change at equivalent time for taking the radiographs and the tissue measurements between the groups. RESULTS. Radiographic and histological analysis showed that there was no difference in marginal bone change between the two groups (P>.05). Histological analysis showed Bioseal group had more rigid connective tissue attachment than the Bevel group. There was no difference in biological width (P>.05). Bevel group showed significantly longer junctional epithelium attachment and Bioseal group showed longer connective tissue attachment (P<.05). CONCLUSION. For three months there were no differences in marginal bone change between the Bevel group and the Bioseal group. As for the soft tissue adjacent to the implant, Bioseal group showed longer connective tissue attachment while showing shorter junctional epithelium attachment. There were no differences in biologic width.

모래층 지반 안벽구조물의 탄성침하거동 연구

유남재,전상현,전진용 江原大學校 産業技術硏究所 2007 産業技術硏究 Vol.27 No.B

This paper is research results of investigating the elastic settlement behavior of the coastal caisson structure built on the sandy deposit by comparing results of centrifuge model experiments and those of existing methods of estimating elastic settlement. Basic soil property tests such as specific gravity test, grain size distribution test and organic content test with disturbed soil sampled from the site were carried out. The centrifuge experiment of model satisfying the required design criteria was performed under 50 of artificial accelerated gravitational force condition. The Centrifuge model experimental results were compared and analyzed with the current methods of estimating settlement based on the elastic modulus obtained from the results of odeometer tests and empirical methods from literature reviews.

한국 진도견의 serum protein 및 lipoprotein 변동에 관한 연구

유상식,이명헌,김상근 충남대학교 수의과대학 동물의과학연구소 1998 動物醫科學硏究誌 Vol.6 No.-

The concentration of serum proteins and lipoproteins in Korean Jindo dogs were examined from the time of after birth to 150 days of age. Eight(4 females and 4 males) Jindo dogs were used in this study. Concentration of serum proteins and lipoproteins were fractioned by cellulose acetate electrophoresis. The results are summarized as follows; 1. The total serum protein concentrations at 1 days(4.6±0.4 g/dl) after birth were lower than in adult dogs, thereafter increased rapidly at 3 days(7.1±0.6 g/dl) of ages, and there was no significant changes between sexes. 2. The concentrations of serum protein from the time of after birth to 150 days of age were 0.35±0.1-8.5±0.2 g/dl and 0.5±0.1-0.8±0.2 g/dl, respectively. The γ-globulin concentrations were not detected 1 days after birth and increased rapidly after pups ingested colostrum(after 3 days of age), thereafter there was no significant changes of γ-globulin concentration after 10 days of age. 3. The concentrations of serum α, β-lipoprtein were not detected 1 days after birth and increased rapidly after pups ingested colostrum(at 3 days of age), from the time of after birth to 150 days of age were 49.1±11.6-94.1±16.4 ㎎/dl and 11.7±6.5-102.0±10.8 ㎎/dl, respectively. 4. the γ-lipoprtein concentrations no detected 1 days after birth and increased rapidly after pups ingested colostrum(at 3 days of age, 11.6±2.5 ㎎/dl) and decreased gradually during 50 days of age, and thereafter increased rapidly during 100-150 days of age(71.8±4.8-77.2±4.1 ㎎/dl).

안벽구조물에 대한 Centrifuge 모형실험과 수치해석

유남재,김동건,전상현 江原大學校 産業技術硏究所 2009 産業技術硏究 Vol.29 No.B

In this paper centrifuge model tests and numerical analysis on the coastal structure on the marine deposits of sand were performed to investigate the behavior of structure and foundation under the condition of wave action in field. In centrifuge model experiments, construction sequence of coastal structure such as preparation of sand deposit, excavation replacement, rubble mound with crushed stones and installment of coastal structure was reconstructed and the behavior of ground settlement during stage of construction was observed during tests. For the final stage of simulating the horizontal movement of coastal structure due to wave force, horizontal load was applied by horizontal loading apparatus being specially designed so that horizontal displacement of structure could be observed. Numerical analysis were also carried out and its results were compared with test results to assess the property of centrifuge mode experiments with respect to the behavior of structure as well as ground.

한국인의 HLA항원과 일배체형의 분포

김현수,황유성,박명희 대한임상병리학회 1997 대한임상병리학회지 Vol.17 No.6

아산시 지역 주민을 대상으로 한 당뇨병의 위험인자에

김유현,김은정,김종명,이성수 순천향의학연구소 2010 Journal of Soonchunhyang Medical Science Vol.16 No.1

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