• 접착 및 계면
• /
• 제23권4호
• /
• pp.116-121
• /
• 2022

Organic field-effect transistor가 실제 전자 장치에 쓰이기 위해서는 유기반도체 용액공정용 미세 패터닝 기술이 요구된다. 본 연구에서는 기존의 스핀 코팅 방법보다 미세 패턴을 형성할 수 있는 소프트 리소그래피 방법이 더 우수한 전기적 특성을 가질 수 있다는 것을 확인하기 위해 비교 분석하였다. Compact Disc 표면의 나노 패턴을 이용하여 유연한 마스터 몰드를 제작하였고, 650 nm 폭의 2,7-Dioctyl [1] benzothieno [3,2-b] [1] benzo thiophene (C_8-BTBT) 나노 와이어를 얻었다. 그 결과 소프트 리소그래피 방법을 이용해 제작된 소자 이동도는 0.086 cm²/Vs이며, 스핀 코팅으로 만들어진 소자 이동도는 0.0036 cm²/Vs으로 소프트 리소그래피 방법으로 제작된 소자가 약 20배 이상 높은 이동도와 더 우수한 전기적 성능을 보였다.

• 호남수학학술지
• /
• 제27권4호
• /
• pp.631-639
• /
• 2005

For compact Hausdorff spaces X and Y let C(X) and C(Y) denote the complex Banach spaces of complex valued continuous functions on X and Y, respectively. Also let $T:C(X){\rightarrow}C(Y)$ be a linear isomerty. Necessary and sufficient conditions are given such that range of T has finite codimension.

• 한국세라믹학회지
• /
• 제34권1호
• /
• pp.95-101
• /
• 1997

평균입경이 22.1$\mu$m인 알루미늄 분말을 사용하여 무가압 분말 충전 성형법으로 52%의 상대밀도를 갖는 성형체를 제조하였다. 산화반응의 활성화 에너지는 TG의 무게 변화로부터 구하였으며, 16~64kJ/mol 범위의 값을 나타내었다. 활성화에너지의 변화와 미세구조의 관찰로부터 산화반응이 산화막의 파괴와 용출에 의존함을 확인하였다. 알루미늄 성형체를 1000~140$0^{\circ}C$에서 4~60시간동안 산화반응시켰을 때, 알루미늄의 산화반응이 시간보다 온도에 의존하였다. 140$0^{\circ}C$에서 60시간동안 산화반응시킨 시편의 산화율은 92%를 나타내었으며, 이 시편을 다시 1$600^{\circ}C$에서 15시간 소결시켰을 때, 소결체는 62%의 상대밀도를 나타내었다.

• ETRI Journal
• /
• 제36권3호
• /
• pp.498-501
• /
• 2014

A C-band 50 W high-power microwave monolithic integrated circuit amplifier for use in a phased-array radar system was designed and fabricated using commercial $0.25{\mu}m$ AlGaN/GaN technology. This two-stage amplifier can achieve a saturated output power of 50 W with higher than 35% power-added efficiency and 22 dB small-signal gain over a frequency range of 5.5 GHz to 6.2 GHz. With a compact $14.82mm^2$ chip area, an output power density of $3.2W/mm^2$ is demonstrated.

• 대한수학회지
• /
• 제43권5호
• /
• pp.991-1018
• /
• 2006

Hypermaps are cellular embeddings of hypergraphs in compact and connected surfaces, and are a generalisation of maps, that is, 2-cellular decompositions of closed surfaces. There is a well known correspondence between hypermaps and co-compact subgroups of the free product $\Delta=C_2*C_2*C_2$. In this correspondence, hypermaps correspond to conjugacy classes of subgroups of $\Delta$, and hypermap coverings to subgroup inclusions. Towards the end of [9] the authors studied regular hypermaps with extra symmetries, namely, G-symmetric regular hypermaps for any subgroup G of the outer automorphism Out$(\Delta)$ of the triangle group $\Delta$. This can be viewed as an extension of the theory of regularity. In this paper we move in the opposite direction and restrict regularity to normal subgroups $\Theta$ of $\Delta$ of finite index. This generalises the notion of regularity to some non-regular objects.

• Kyungpook Mathematical Journal
• /
• 제48권3호
• /
• pp.487-493
• /
• 2008

A. Di Nola & S.Sessa [8] showed that two compact spaces X and Y are homeomorphic iff the MV -algebras C(X, I) and C(Y, I) of continuous functions defined on X and Y respectively are isomorphic. And they proved that A is a semisimple MV -algebra iff A is a subalgebra of C(X) for some compact Hausdorff space X. In this paper, firstly by use of functorial argument, we show these characterization theorems. Furthermore we obtain some other functorial results between topological spaces and MV -algebras. Secondly as a classical problem, we find a necessary and sufficient condition on a given residuated l-monoid that it is segmenently embedded into an l-group with order unit.

• Journal of information and communication convergence engineering
• /
• 제6권4호
• /
• pp.405-410
• /
• 2008

This paper presents a data acquisition and monitoring system for a gas turbine. The proposed system entitled C-Tune DAS plays an important role to make an analysis of the real-time operation of the gas turbine under maintenance. The designed LabVIEW based software is divided into three parts according to their original functions, i.e., data acquisition, data analysis with display, and data storage. The data acquisition part receives data from a PMS (Plant Management System) server and two cFPs (Compact-Field Point). To verify the validity of the developed system, it is applied to gas turbines in the combined cycle power plant in Korea.

• 대한수학회논문집
• /
• 제11권2호
• /
• pp.377-383
• /
• 1996

For a given separable space X which contains no copy of $C_0$ and a weakly compact T, we show that a Dunford integrable function $f : [a,b] \to X$ is intrinsically-separable valued if and only if f is McShane integrable. Also, for a given separable space X which contains no copy of $C_0$, a weakly compact T and a Dunford integrable function f we show that if there exists a sequence $(f_n)$ of McShane integrable functions from [a,b] to X such that for each $x^* \in X^*, x^*f_n \to x^*f$ a.e., then f is McShane integrable. Finally, let X contain no copy of $C_0$. If $f : [a,b] \to X$ is McShane integrable, then F is a countably additive on $\sum$.

• 대한수학회지
• /
• 제55권3호
• /
• pp.735-747
• /
• 2018

Let M be a real hypersurface of a complex space form with constant curvature c. In this paper, we study the hypersurface M admitting Miao-Tam critical metric, i.e., the induced metric g on M satisfies the equation: $-({\Delta}_g{\lambda})g+{\nabla}^2_g{\lambda}-{\lambda}Ric=g$, where ${\lambda}$ is a smooth function on M. At first, for the case where M is Hopf, c = 0 and $c{\neq}0$ are considered respectively. For the non-Hopf case, we prove that the ruled real hypersurfaces of non-flat complex space forms do not admit Miao-Tam critical metrics. Finally, it is proved that a compact hypersurface of a complex Euclidean space admitting Miao-Tam critical metric with ${\lambda}$ > 0 or ${\lambda}$ < 0 is a sphere and a compact hypersurface of a non-flat complex space form does not exist such a critical metric.

• 한국분말재료학회지
• /
• 제13권1호
• /
• pp.39-45
• /
• 2006

The $Al/SiC_p$ particle reinforced composite fabricated by a powder-in sheath rolling (PSR) method was severely. deformed by the accumulative roll-bonding (ARB) process. The ARB process was performed up to 8 cycles at ambient temperature without lubricant. The ARBed composite exhibited an ulbricant. grained structure similar to the other ARBed bulky materials. Tensile strength of the composite increased gradually with the number of ARB cycles, but from the 6th cycle it rather decreased slightly. These characteristics of the composite were somewhat different from those of Al powder compact fabricated by the same procedures. The difference in microstructure and mechanical properties between Al powder compact and the composite was discussed.