• Archives of Reconstructive Microsurgery
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• 제23권1호
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• pp.1-7
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• 2014

Purpose: Recent studies have reported on application of fibrin glue composed of fibrinogen and thrombin to nerve anastomosis, which can be another candidate for vessel anastomosis. However, no research regarding the risk and effectiveness of thrombin in microvascular free tissue transfer has been reported. Therefore, the aim of study is to determine the risk and effectiveness of thrombin on microvascular free tissue transfer through clinical cases. Materials and Methods: Twenty-five patients underwent free flap reconstruction for soft tissue defect or bone exposure in our institute from March 2011 to February 2014. In the group using thrombin, dissolved powder thrombin (5,000 IU/amp) was mixed with 10 mL normal saline. Saline mixed with thrombin was applied on the flap, recipient, and around vessel anastomosis. In the control group, free flap was performed using the same method, except using thrombin. We analyzed the results between the two groups. Results: All flaps survived. The group using thrombin included 14 patients and the control group included 11 patients. Hematoma was found in two cases, respectively, in each group. The group using thrombin showed lower incidence of hematoma than the control group. No difference in survival rate of the flap was observed between the thrombin group and the control group. Conclusion: Results of this study showed that use of saline mixed with thrombin in free tissue transfer may be safe and effective for prevention of hematoma formation in the recipient site.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1992년도 추계학술대회 논문집
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• pp.28-30
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• 1992

Long incubation period of W nucleation on the TiN glue layer is a serious problem in blanket W process. In this study we investigated the dependence of W nucleation and growth rate on the preparation method of the TiN film, deposition temperature, chemistry, $SiH_4/WF_6$ ratio and sputter etching, ion implantation, and $SiH_4$ flushing pre-treatments. Incubation periods of W nucleation and deposition rates of W growth on three different TiNs are in the order of TiN>RTP-TiN> annealed TiN and TiN${\leq}$RTP-TiN${\leq}$ annealed TiN, respectively. $\beta$-W is not found on TiN substrate even for high $SiH_4/WF_6$ ratio. Sputter etching pre-treatment increases incubation period of W nucleation, while it decreases deposition rate. $SiH_4$ flushing pre-treatment decreases incubation period, but it slightly decreases deposition rate.

• 한국수산과학회지
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• 제36권5호
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• pp.469-473
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• 2003

Transplantation of Sargassum horneri to natural substrate using the rope seeding method was undertaken. Seeding of S. horneri was grown on net in an indoor tank up to 0.2-0.3 cm in frond length for 2 months, and then transplanted to an architecture tile $(10\times10\;cm)$ with underwater glue and an iron pipe. After two months, number of S. horneri on the tile decreased because of grazing by herbivores. However, S. horneri on the iron pipe grew up to 0.5-2.0 cm in frond length. After 7 months, they rapidly grew up to a frond length of 11.0-203.0 cm with a mean frond length of 122.6 cm. S. horneri grew up to a maximum frond length of 313.0 cm, and mean frond length of 228.0 cm, after 10 months. The artificial S. hornevi beds can be used to clean the seawater and also be utilized as a source of marine biomass as well as for supplying habitat, shelter and spawning beds for fish and invertebrates.

• Structural Engineering and Mechanics
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• 제74권1호
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• pp.145-156
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• 2020

There are separate merits and demerits to wood and steel. The combination of wood and steel as a compound section is able to improve the properties of both and ultimately increase their final bearing capacity. The composite cross-section made of steel and wood has higher hardness while showing more ductility and the local buckling of steel is delayed or completely prevented. The purpose of this study is to investigate the behavior of composite columns enclosed in wooden logs and the hollow sections of steel that will be examined in a laboratory environment under the axial load to determine the final bearing capacity and sample deformation. In terms of methodology, steel sheet and carbon fiber reinforced polymer sheet (FRP) are tested to construct hollow rectangular sections and reinforce timber. Besides, the method of connecting hollow sections and timber including glue and screw has been also investigated. As a result, timber lumber enclosed with carbon fiber-reinforced polymer sheets in which fibers are horizontally located at 90° are more resistant with better ductility.

• 한국가구학회지
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• 제18권2호
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• pp.91-99
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• 2007

Modernity which is superficial phenomenon set off the mass scale for mass consumption and provide uniformly artificial environment. But natural destruction, environment pollution, resources exhaustion and so on has been caused by this and now ecology is threatened by destruction and damage beyond the limitation and human beings survival is even threatened. Accordingly furniture development for environment preservation considered environment problem is the urgent real situation. Recent paradigm is the concept of Eco-design which is the green design possible to live together in symbiosis, and new types of alternative furniture are needed in Korea as well. 'Furniture for disassembly' is presented as new method for alternative furniture. Furniture for disassembly can be presented by mainly two directions. The first main characteristic is what is assembled by the use of woodworking joints technique as an assembly structure system without any hardware. The second is what is presented as the structure possible to be assembled by simple manual tools with hardware without any glue. The advantages of furniture for disassembly are environment preservation, space application, transportation efficiency and shapeliness. In manufacture method which is different from present furniture, the application of traditional truss technique which uses various types of custom-made and connection technique in case of assemble structure system without hardware is the typical differences. This assembly method expects not only interest induction about assembly and disassembly of diagram per sub materials but also the development of emotion, the improvement of collaboration, space perception ability and shape sense, the improvement of solid body structure insight and so on, when it use in the furniture for children with the application to many kinds of structure with BANGDOOSANJ (Wedged), JUMUGJANGBU (Dovetail) or NABIEUNJANG (Dovetail Keys) and so on.

• 접착 및 계면
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• 제5권2호
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• pp.22-36
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• 2004

Several in-situ testing methods of adhesively bonded joints under static short-time tensile loading are critically analyzed in terms of experimental procedure and data evaluation. Due to its rather homogeneous stress state across the glue line, the tensile-shear test with thick single-lap specimens, according to ISO 11003-2, has become the most important test process for the determination of realistic materials parameters. This basic method, which was improved in both, the experimental part by stepped adherends and easily attachable extensometers and the evaluation procedure by numeric substrate deformation correction and test simulation based on the finite element method (FEM), is therefore demonstrated by application to several kinds of adhesives and metallic adherends. Multi-axial load decreases the strength of a joint. This effect, which is illustrated by an experimental comparison, impedes the derivation of realistic mechanical characteristics from measured force-displacement curves. It is shown by numeric modeling that tensile-shear tests with thin plate substrates according to ISO 4587, which are widely used for quick industrial quality assurance, reveal an inhomogeneous stress state, especially because of relatively large adherend deformation. Complete experimental determination of the elastic properties of bonded joints requires independent measurement of at least two characteristics. As the thick-adherend tensile-shear test directly yields the shear modulus, the tensile butt-joint test according to ISO 6922 represents the most obvious complement of the test programme. Thus, validity of analytical correction formulae proposed in literature for the derivation of realistic materials characteristics is verified by numeric simulation. Moreover, the influence of the substrate deformation is examined and a FEM correction method introduced.

• 한국건축시공학회지
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• 제2권2호
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• pp.129-134
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• 2002

The strength and durability of concrete are affected by various factors such as the quality of material, mixing ratio, construction, the method of cure, time elapsed. the condition of test and etc., it is very difficult to pre-estimate the strength of concrete with the use of experimental specimen. The domestic standard of specimen cylindrical type and its sizes are both l0cm$\times$20cm and 15cm$\times$30cm, which are prescribed in KS F2405, and the loading speed is prescribed to test with 2~3kgf/$\textrm{cm}^2$ per second. The loading speed should have great effect on the compressive strength, but in reality in the construction site sometimes the loading speed is applied so dubiously that the value of the compressive strength can be unreliable. And the cross sectional area of a specimen should be level and smooth, otherwise it can be broken at a lower stress than the real strength through the eccentric or intensive working of the load. Capping should be carried out in order to measure the strength correctly. And used for capping are various materials such as capping compound, cement glue, plaster, mechanical grinding and etc. In this study, therefore, I have carried out an experiment on the relationship among the loading speed, the ratio of height to diameter of specimen, the method of capping, and the compressive strength, for the efficient quality control of concrete structures. So this study has been purposed to provide some basic data that can be used effectively at construction sites.

• 한국재료학회지
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• 제3권5호
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• pp.466-475
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• 1993

전면증착법에 의한 W공정에서 부착특성고양층으로 사용되는 TiN막에 대한 CVD W막의 부착특성을 인장법(pulling method)과 스크래치법(scratch method)을 사용하여 조사하고, 주사전자현미경과 반사도측정에 의한 표면거칠기측정, 응력측정 및 SIMS depth profiling 등에 의하여 그 원인을 분석하였다. 스퍼터링법으로 형성한 TiN막상에 바로 W막을 증착한 경우와 TiN막을 열처리한 후에 W막을 증착한 경우 간에 두 막간의 부착특성은 큰 차이를 보였다. 전자의 경우가 후자의 경우보다 부착특성이 더 우수한 것으로 나타났는데, 이것은 열처리하지 않은 TiN막이 열처리한 TiN막에 비해 표면이 더 거칠고, 응력수준이 더 낮으며, 열처리한 TiN막내에는 산소성분이 존재하는 반면, 열처리 하지 않은 TiN막내에는 산소성분이 거의 들어있지 않기 때문이다. 또한 TiN막 두께가 증가함에 따라 응력의 증가로 인하여 TiN막에 대한 W막의 부착강도가 저하되었다.

• 분석과학
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• 제17권6호
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• pp.443-453
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• 2004

톨루엔은 환각성 유기용매로서 청소년에 의하여 남용되는 본드류에서 주성분으로 사용되고 있다. 본 연구에서는 Headspace 가스크로마토그래프 방법에 의한 톨루엔 남용자들의 혈액, 소변, 타액에서 톨루엔을 분석하는 방법을 확립하기 위하여 측정 방법의 유효화와 측정에 관련된 불확도를 추정하였다. 혈액, 소변, 타액 시료 중에서 검출한계는 타액에서 $0.01{\mu}g/mL$로, 정량한계는 혈액에서 $0.1{\mu}g/mL$로 가장 높았다 (N=5). 각 생체시료에 대한 유효화의 다른 주요 인자들인 직선성, 분석농도범위, 정확도, 정밀도, 회수율 등도 측정하였다. 톨루엔 $1{\mu}g/mL$의 농도에서 혈액, 소변, 타액 시료의 톨루엔 분석방법에 대한 불확도는 각각 0.13, 0.09, $0.17{\mu}g/mL$로 추정되었고, 추정된 불확도의 성분들 중에서 낮은 농도에서는 검량선에 대한 불확도가 가장 큰 비중을 차지하고 있었다.

• 한국방사선학회논문지
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• 제15권6호
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• pp.855-860
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• 2021

커피는 국내뿐만 아니라 전 세계인들에게 인기 있는 음료로서 그 소비는 점점 늘어나는 추세에 있다. 커피 소비 증가는 커피를 추출하고 발생되는 커피 찌꺼기 또한 증가하고 있으며, 다양한 분야로 재활용을 시도하고 있다. 그러나 이러한 재활용 방법들은 재활용 과정들이 복잡하고 전문적인 기술을 필요로 한다. 하지만 본 연구에서는 커피 찌꺼기, 한천분말, 가루풀을 적정 비율로 배합하여 시멘트 건축마감 재료로 활용하였다. 본 재활용 방법은 제조 방법이 간단하고 시멘트벽에서 방출되는 라돈을 1회 바름으로 2.5시간, 2회 바름으로 3.9시간을 지연시켜 실내 공기질을 향상시킬 수 있는 것으로 나타났다. 또한 커피 찌꺼기 혼합물을 바른 후 건조과정에서 발생하는 균열을 매우기 위하여 2회 바름으로서 미관적인 완성도와 벽면에서 커피 찌꺼기가 탈락되는 것을 방지할 수 있는 것으로 나타났다.