• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.6
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• pp.609-617
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• 2011

There is a trend towards the progressive use of higher operating temperatures and stresses to achieve improved efficiencies in power-generation equipment. It is important to perform the crack assessment under hightemperature and high-pressure conditions. The C(t)-integral is a key parameter in crack assessment for transient creep states. The estimation of the C(t)-integral is complex when considering the mechanical and thermal loads simultaneously. In this paper, we study estimation of C(t)-integral under combined mechanical and thermal load depending on loading conditions.

• Microbiology and Biotechnology Letters
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• v.5 no.3
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• pp.133-140
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• 1977

The results of electron microscopic studies on the cell fine structure of Nocardia sp the location of tellurite-reducing enzyme and the reduction part of T. T. C. (Triphenyl tetrazonium chloride) were summarized as follows. As the fine structure of the cell, the membrane-like structure with unit membrane was distributed in the cytoplasm. The membrane-like structure had complicate forms: some of membrane-like structure appeared spiral form. As the metal tellurium salt appeared in the cytoplasm, it is obvious that tellurite and tellurate-reducing enzymes are present in the cytoplasm. Reduction of T. T. C. took place in the cell membrane and the intracellular membrane-like structure. Therefore, it was thought that reduction of tellurate and T. T. C. took place in different parts. T. T. C. formazane formed in the cell was reoxidized by osmic acid which was used as a fixation reagent for the electron microscopic specimen preparation. As 95％ T. T. C. formazane was soluble in ethanol and embedding materials and removed out of the cell, an originally formed formazane appeared as electron light part on the electron microscopic image.

• Korean Journal of Community Nutrition
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• v.12 no.3
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• pp.223-234
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• 2007

This study was done to determine the trans fatty acid (tFA) composition of human milk from postpartum to sixth months after delivery, to investigate the tFA intake of lactating women, and to estimate the intakes of tFA by infants exclusively fed breast milk. A total of 27 lactating Korean women participated to this study voluntarily, gave their breast milk, and responded to an investigation of their diets. The lactating women consumed 2.3-2.8 g/d of tFAs over the period of the first, second, third, and sixth months postpartum, which was 3.4-4.9% of the total fat intake and 0.8%-1.2% of the total energy intake. The proportions of tFAs in the breast milk were 1.89% in colostrum, 1.78% in transitional milk, and 1.78-2.25 in mature milk of the first, second, third, and sixth months postpartum. The tFAs of the breast milk identified in this study were C16:1n9t, C18:1n9t, C18:2n6t12t, C18:2n6t12c, C18:2n6t12t and C18:2n6t11t. Among them, C18:1n9t was predominant, which made up 59.26% of all tFAs in cob strum, 62.36% in transitional milk, and 64.42% in mature milk. The proportion of total tFA was unchanged with time, although some significant differences were noted for individual tFAs. The percentages of C18:2n6t12c and C18:2n6c12t decreased over the study period. Estimated tFA intake of the exclusively breast-fed infants was 0.18 g/d when fed colostrum, 0.29 g/d when fed transitional milk, and 0.53 g/d when fed mature milk until the sixth month of postpartum. Those were 0.5%, 0.8%, and 1.1% of the total energy intake. The results in this study indicate that lactating Korean women consume not a large quantity of tFAs, secrete breast milk not containing much tFA, and the estimated intake of tFAs by infants fed exclusively breast milk is not great.

• Communications of the Korean Mathematical Society
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• v.30 no.2
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• pp.65-72
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• 2015

The minimum rank mr(G) of a simple graph G is defined to be the smallest possible rank over all symmetric real matrices whose (i, j)-th entry (for $i{\neq}j$) is nonzero whenever {i, j} is an edge in G and is zero otherwise. The corona $C_n{\circ}K_t$ is obtained by joining all the vertices of the complete graph $K_t$ to each n vertex of the cycle $C_n$. For any t, we obtain an upper bound of zero forcing number of $L(C_n{\circ}K_t)$, the line graph of $C_n{\circ}K_t$, and get some bounds of $mr(L(C_n{\circ}K_t))$. Specially for t = 1, 2, we have calculated $mr(L(C_n{\circ}K_t))$ by the cut-vertex reduction method.

• Journal of Animal Science and Technology
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• v.49 no.1
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• pp.25-32
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• 2007

The current study was undertaken to determine the effect of conjugated linoleic acid(CLA) isomers, cis-9, cis-11(c9c11), cis-9, trans-11(c9t11), trans-9, trans-11(t9t11), trans-10, cis-12(t10c12) on differentiation of pig preadipocytes and myogenic satellite cells during culture. Cells were isolated from new born pigs. The t10c12 isomer decreased differentiation of pig preadipocytes(92%), but not that of myogenic cells. The t9t11 isomer decreased differentiation of preadipocytes(14%) and increased that of myogenic cells (26%). No other CLA isomers affected differentiation of preadipocytes or myogenic cells. The effects of CLA on proliferation of preadipocytes and myogenic cells were small, compared to the effects on differentiation. These results suggest that CLA isomers have different effects on differentiaton of pig preadipocytes and myogenic cells.

• Journal of the Korean Chemical Society
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• v.24 no.3
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• pp.250-258
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• 1980

Various radicals may add to isonitriles to give imidoyl radcals RN=CR'. This may be also generated via abstraction of imidoyl hydrogen from imine in the following manner: RN=CR' ＋ R"${\cdot}{\rightarrow}$ RN=CR' ＋ R"-H Imidoyl radicals would be stabilized via two pathways, ${\beta}$-cleavage and atom transfer reactions. ${\beta}$-Cleavage may occur in two directions depending upon structure of the radicals. Cyanide transfer and the "so-called" normal ${\beta}$-cleavage are the two modes of ${\beta}$-cleavage. Addition of t-butoxy radical to t-butyl isocyanide 7 generates an imidoyl radical t-Bu-N=C-O-Bu-t, which undergoes ${\beta}$-cleavage to give t-butyl isocyanate and t-butyl radical. Addition of phenyl radical to 7 forms the intermediate radical t-Bu-N=$C-C_6H_5$, which decomposes to give benzonitrile and t-butyl radical. The t-butyl radical generated from the ${\beta}$-cleavage adds to 7 giving the radical t-Bu-N=C-Bu-t, which cleaves only to pivalonitrile and t-butyl radical, inducing radical chain isomerization. Trimethylsilyl radical adds to 7 to give the intermediate t-Bu-N=$C-Si(CH_3)_3$, which collapses to $(CH_3)_3$SiCN and a t-butyl radical.

• Kyungpook Mathematical Journal
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• v.52 no.4
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• pp.413-431
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• 2012

Let $C^r[0,t]$ be the function space of the vector-valued continuous paths $x:[0,t]{\rightarrow}\mathbb{R}^r$ and define $X_t:C^r[0,t]{\rightarrow}\mathbb{R}^{(n+1)r}$ and $Y_t:C^r[0,t]{\rightarrow}\mathbb{R}^{nr}$ by $X_t(x)=(x(t_0),\;x(t_1),\;{\cdots},\;x(t_{n-1}),\;x(t_n))$ and $Y_t(x)=(x(t_0),\;x(t_1),\;{\cdots},\;x(t_{n-1}))$, respectively, where $0=t_0$ < $t_1$ < ${\cdots}$ < $t_n=t$. In the present paper, using two simple formulas for the conditional expectations over $C^r[0,t]$ with the conditioning functions $X_t$ and $Y_t$, we establish evaluation formulas for the analogue of the conditional analytic Fourier-Feynman transform for the function of the form $${\exp}\{{\int_o}^t{\theta}(s,\;x(s))\;d{\eta}(s)\}{\psi}(x(t)),\;x{\in}C^r[0,t]$$ where ${\eta}$ is a complex Borel measure on [0, t] and both ${\theta}(s,{\cdot})$ and ${\psi}$ are the Fourier-Stieltjes transforms of the complex Borel measures on $\mathbb{R}^r$.

• Biomedical Science Letters
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• v.6 no.2
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• pp.131-139
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• 2000

RAPD-PCR was applied to identify the phylogenetic relationship between isolated Korean-type coliphages ($\phi$C1, $\phi$C2, $\phi$C3 and $\phi$C4) and well-known American coliphages ($\phi$T2, $\phi$T4, $\phi$T5, $\phi$T7 and ${\phi}{\lambda}$). Subsequently, a computer analysis was carried out with the results of RAPD-PCR. As a result, 9 individuals were divided into five groups. The Korean-type coliphages formed a single cluster which showed very high genetic similarity but the American-type coliphages revealed very low genetic similarity among them. In particular, the $\phi$T2와 $\phi$T4 (T$_{even}$ phages) made one sub-cluster among American coliphages, and they were very distant from $\phi$T5, $\phi$T7 and ${\phi}{\lambda}$. However, ${\phi}{\lambda}$ made a cluster with the Korean-type coliphages that we isolated. The genome size of Korean-type coliphages was ranged from 25,000 bp to 35,000 bp. Among them, the genome of $\phi$C2 was the smallest and that of $\phi$C1 was the biggest, while others were in the middle of the size.

• Journal of Aquaculture
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• v.4 no.1
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• pp.13-18
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• 1991

In order to obtain basic biological data for effective seed production of the red sea bream, Pargus major, the influence of water temperature on egg development was investigated. The time of egg development was shorter with higher water temperature. The relationships between the water temperature($T\;:\;^{\circ}C$) and the required time(t : hour) from egg to each developmental stage were given as follows : 8-cell 1/t=0.0618T-0.5877(r=0.9899) Morula : 1/t=0.0284T-0.2556(r=0.9948) Kupffer's : 1/t=0.0076T-0.0829(r=0.9902) vesicle Hatching : 1/t=0.0031T-0.0350(r=0.9985) Biological minimium temperature for the egg development was estimated to be $10.2^{\circ}C$ in average.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.185-189
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• 1987

Reactions of $Ir(ClO)_4(CO)(PPh_3)_2$ with dicyano olefins, cis-NCCH = CH$CH_2$$CH_2$CN (cDC1B), trans-NCCH = CH$CH_2$$CH_2$CN (tDC1B), trans-NC$CH_2$CH = CH$CH_2$CN (tDC2B), and NC$CH_2$$CH_2$$CH_2$$CH_2$CN (DCB) produce binuclear dicationic iridium (I) complexes, $[(CO)(PPh_3)_2Ir-NC-A-CN-Ir(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (1a), tDC1B (1b), tDC2B (1c), DCB (1d)). Complexes 1a-1d react with hydrogen to give binuclear dicationic tetrahydrido iridium (Ⅲ ) complexes, $[(CO)(PPh_3)_2(H)_2Ir-NC-A-CN-Ir(H)_2(PPh_3)_2(CO)](ClO_4)_2$ (NC-A-CN = cDC1B (2a), tDC1B (2b), tDC2B (2c), DCB (2d)). Complexes 2a and 2b catalyze the hydrogenation of cDC1B and tDC1B, respectively to give DCB, while the complex 2c is catalytically active for the isomerization of tDC2B to give cDC1B and tDC1B and the hydrogenation of tDC2B to give DCB at $100^{\circ}C$.