• 한국재료학회지
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• 제8권3호
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• pp.263-267
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• 1998

본 연구에서는 금속 칼날 마스크와 펄스형 레이저 증착장치를 이용하여 $YBa_2Cu_3O_{7-\delta}$/$SrTiO_{3}$/$YBa_2Cu_3O_{7-\delta}$ 다층박막 형태의 In-situ SIS ramp dege 형태의 접합을 제작하였으며, 이의 특성을 조사하였다. 접합은 RSJ 형태의 전류-전압 특성ㅇ르 나타내고 있으며, 온도 변화에 따른 접합의 normal resistance는 약 $18 \omega$으로 온도에 무관하게 일정한 값을 나타내었다. 접합형태를 이용하여 감도(transfer function, dV/$d\Phi$)가 약 $22\mu$V/$\Phi_{0}$인 dc-SQUID센서를 제작하였으며, in-situ SIS ramp edge 형태의 접합이 센서로의 응용가능성을 충분히 가지고 있음을 보여 주었다.

• 미생물학회지
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• 제44권2호
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• pp.105-109
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• 2008

발아효모 Saccharomyces cerevisiae의 핵공단백질인 Nic96 단백질과 유사성을 보이는 분열효모 Schizosaccharomyces pombe의 Nup97의 기능과 세포 내 위치를 조사하였다. nup97을 과 발현시켰을 때는 생장과 $poly(A)^{+}$ RNA의 분포에 별다른 이상을 보이지 않았다. 하지만, $kan^{r}$ 유전자를 이용하여 제작한 ${\Delta}nup97$ 결실돌연변이는 nup97의 발현이 억제되면, $poly(A)^{+}$ RNA가 핵 안에 축적되었고 비정상적인 DNA 분포를 보였으며 결국 생장하지 못했다. 한편, Nup97p의 N말단 또는 C말단에 GFP를 붙인 Nup97-GFP 융합단배질의 세포 내 위치를 확인하고자 하였다. 이러한 융합단백질들이 ${\Delta}nup97$ 결실돌연변이의 생장결함을 정상적으로 상보하는 것을 확인하고, nup97-GFP 유전자를 염색체의 nup97 유전자 위치에 삽입한 균주를 제작하였다. 자신의 프로모터에서 발현된 Nup97-GFP 융합단백질은 정상적인 기능을 보였으며, 핵막 주위에 점점 이 위치하였다. 이와 같은 결과들은 Nup97 단백질 역시 핵공단배질로 mRNA의 핵에서 세포질로의 이동에 중요하다는 것을 시사한다.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1288-1298
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• 2019

Bacterial ATP synthases drive ATP synthesis by a rotary mechanism, and play a vital role in physiology and cell metabolism. Corynebacterium glutamicum is well known as an industrial workhorse for amino acid production, and its ATP synthase operon contains eight structural genes and two adjacent genes, cg1360 and cg1361. So far, the physiological functions of Cg1360 (GenBank CAF19908) and Cg1361 (GenBank CAF19909) remain unclear. Here, we showed that Cg1360 was a hydrophobic protein with four transmembrane helices (TMHs), while no TMH was found in Cg1361. Deletion of cg1360, but not cg1361, led to significantly reduced cell growth using glucose and acetic acid as carbon sources, reduced F1 portions in the membrane, reduced ATP-driven proton-pumping activity and ATPase activity, suggesting that Cg1360 plays an important role in ATP synthase function. The intracellular ATP concentration in the ${\Delta}cg1360$ mutant was decreased to 72% of the wild type, while the NADH and NADPH levels in the ${\Delta}cg1360$ mutant were increased by 29% and 26%, respectively. However, the ${\Delta}cg1361$ mutant exhibited comparable intracellular ATP, NADH and NADPH levels with the wild-type strain. Moreover, the effect of cg1360 deletion on L-valine production was examined in the L-valine-producing V-10 strain. The final production of L-valine in the $V-10-{\Delta}cg1360$ mutant reached $9.2{\pm}0.3g/l$ in shake flasks, which was 14% higher than that of the V-10 strain. Thus, Cg1360 can be used as an effective engineering target by altering energy metabolism for the enhancement of amino acid production in C. glutamicum.

• 충청수학회지
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• 제26권4호
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• pp.879-885
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• 2013

In this paper, we de ne an extension $f^*:[a,b]{\rightarrow}\mathbb{R}$ of function $f^*:[a,b]_{\mathbb{T}}{\rightarrow}\mathbb{R}$ for a time scale ${\mathbb{T}}$ and prove the convergence theorems for the Henstock delta integral on time scales.

• 충청수학회지
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• 제27권1호
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• pp.113-121
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• 2014

In this paper, we define an extension $f^*:[a,\;b]{\rightarrow}\mathbb{R}$ of a function $f:[a,\;b]_{\mathbb{T}}{\rightarrow}\mathbb{R}$ for a time scale $\mathbb{T}$ and show that f is McShane delta integrable on $[a,\;b]_{\mathbb{T}}$ if and only if $f^*$ is McShane integrable on [a, b].

• 약학회지
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• 제36권6호
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• pp.577-581
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• 1992

Norfloxacin complexes of $Fe^{2+}$, $Cu^{2+}$ and $Al^{3+}$ have been prepared as solids. The stoichiometry of the complexes has been established. IR investigation indicates the metal-ligating sites in norfloxacin. The bioactivities of complexes all lower than that of norfloxacin. The solubilities and partition coefficients have been measured as a function of temperature. The data are used to evaluate the thermodynamic parameters ${\Delta}G$, ${\Delta}H$, ${\Delta}S$ for the solute transfer process and compared with the parent quinolone, norfloxacin. The existence of such complexes is discussed in the light of quinolone mode-of-action theories.

• 한국해양공학회지
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• 제9권2호
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• pp.112-122
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• 1995

In this work, prediction of fatigue life and fatigue crack growth are studied. 4th order polynominal function is presented to describe the crack growth behaviors from artifical pit of SM45C steel. Crack growth curves obtained from 4th order polyminal growth equations are in good agreement with experimental data The crack growth behaviors at arbitrary stress levels and investigated by the concept of elastic-plastic fracture mechanics using ${\Delta}J$. Fatigue life prediction are carried out by numerical integral method. Prediction lives obtained by proposed method in this study, is in good agreement with the experimental ones. Life prediction results calculated by using of ${\Delta}J$ better than those of ${\Delta}K$.

• 한국세라믹학회지
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• 제32권3호
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• pp.394-402
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• 1995

Electrical conductivity and thermoelectric power of the ferrous ferrite system of (Mg0.29-yMnyFe0.71)3-$\delta$O4 have been measured as function of the thermodynamic variables, cationic composition(y), temperature(T) and oxygen partial pressure(Po2) under thermodynamic equilibrium conditions at elevated temperatures. On the basis of the electrical properties-phase stability correlation, the stability regions of the ferrite spinel and its neighboring phases have been subsequently located in the log Po2 vs. y and log Po2 vs. 1/T planes in the ranges of 0 y 0.29, 1100 T/$^{\circ}C$ 1400 and 10-14 Po2/atm 1. The stability region, Δlog Po2(y, 1/T), of the ferrite spinel single phase widens with increasing Mn-content(y) and the boundaries of each region are linear against 1/T with negative slopes.

• 대한수학회보
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• 제51권6호
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• pp.1829-1839
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• 2014

Let (${\Omega}$, $\mathcal{S}$, ${\mu}$) be a probabilistic measure space, ${\varepsilon}{\in}\mathbb{R}$, ${\delta}{\geq}0$, p > 0 be given numbers and let $P{\subset}\mathbb{R}$ be an open interval. We consider a class of functions $f:P{\rightarrow}\mathbb{R}$, satisfying the inequality $$f(EX){\leq}E(f{\circ}X)+{\varepsilon}E({\mid}X-EX{\mid}^p)+{\delta}$$ for each $\mathcal{S}$-measurable simple function $X:{\Omega}{\rightarrow}P$. We show that if additionally the set of values of ${\mu}$ is equal to [0, 1] then $f:P{\rightarrow}\mathbb{R}$ satisfies the above condition if and only if $$f(tx+(1-t)y){\leq}tf(x)+(1-t)f(y)+{\varepsilon}[(1-t)^pt+t^p(1-t)]{\mid}x-y{\mid}^p+{\delta}$$ for $x,y{\in}P$, $t{\in}[0,1]$. We also prove some basic properties of such functions, e.g. the existence of subdifferentials, Hermite-Hadamard inequality.

• 대한수학회보
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• 제50권4호
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• pp.1061-1067
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• 2013

In this paper, we study surfaces of revolution without parabolic points in 3-Euclidean space $\mathbb{R}^3$, satisfying the condition ${\Delta}^{II}G=f(G+C)$, where ${\Delta}^{II}$ is the Laplace operator with respect to the second fundamental form, $f$ is a smooth function on the surface and C is a constant vector. Our main results state that surfaces of revolution without parabolic points in $\mathbb{R}^3$ which satisfy the condition ${\Delta}^{II}G=fG$, coincide with surfaces of revolution with non-zero constant Gaussian curvature.