• Communications of the Korean Mathematical Society
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• v.12 no.3
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• pp.603-617
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• 1997

Consider a Sobolev inner product on the space of polynomials such as $$ \phi(p,q) = \lambda p(c)q(c) + <\tau,p'(x)q'(x)> $$ where $\tau$ is a moment functional and c and $\lambda$ are real constants. We investigate properties of orthogonal polynomials relative to $\phi(\cdot,\cdot)$ and give necessary and sufficient conditions under which such Sobolev orthogonal polynomials satisfy a spectral type differential equation with polynomial coefficients.

• Proceedings of the KIPE Conference
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• 2012.11a
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• pp.185-186
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• 2012

본 논문에서는 HVDC C&P(High Voltage Direct Current Control and Protection) 시스템의 네트워크 이중화 방법을 제안한다. 본 논문에서 제안하는 HVDC C&P 시스템 네트워크 이중화 방법은 2개의 이더넷 라인을 제어기에 직접 연결하고, 연결된 라인으로 동시에 정보를 송신하여, 제어기에서 정보를 필터링하여 사용하는 방법을 사용한다. 또한 네트워크 라인의 효과적인 결선 체크를 위해 제어기간 송수신을 통해 네트워크 라인의 결선을 체크하는 방법을 사용한다. 위와 같은 방법은 HVDC C&P 시스템의 네트워크 안정성을 향상시키는 효과를 기대할 수 있다.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.10a
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• pp.163-168
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• 1991

최근 도시지역에서의 교량가설시 P.C BOX GR. 교량이 차지하는 비율이 점차 증가하면서 도심교통난 유발을 최소화 할 수 있는 가설공법에 대한 필요성이 증대되고 있는 상황에서 Precast Element를 이용하여 P.C BOX GR.의 Cantilever 길이를 길게하여 MAIN BOX GR.의 폭을 감소시켜 광폭(B=20M이상)의 상부구조물 일지라도 하부구조를 일주식 교각으로 설치가능할 뿐만 아니라 MAIN BOX GR. 가설시 어떤 가설공법도 적용가능하므로 현장여건에 가장 적합한 가설공법을 용이하게 P.C BOX GR. 공법을 소개하고자 한다.

• Korean journal of food and cookery science
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• v.27 no.3
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• pp.21-28
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• 2011

In this study, we analyzed flower tea activity against oral bacteria. Lagerstroemia indica, Paeonia suffruticosa and Hemerocallis fulva showed high extract yields. Bellis perennis, Punica granatum and Cercis chinensis showed the high rates of yield by ethanol extraction. Extract yield seemed to be related to the characteristics of the specimens rather than to the solvent. Streptococcus mutans, Streptococcus obrinus, Porphyromonas gingivalis and Prevotella intermedia were used to investigate extracts activity against bacteria; the former two cause dental caries and the latter two cause halitosis. Cornus officinalis, L. indica, P. granatum and P.s uffruticosa showed high antibacterial activities against S. mutans. In specimens extracted with ethanol, P. suffruticosa, Camellia sinensis, Camellia japonica L. and Rosa hybrida showed high antibacterial activities. L. indica, P. granatum and C. officinalis showed high antibacterial activities against S. sobrinus. C. officinalis, P. granatum, L. indica and P. suffruticosa showed high activities for specimens extracted with ethanol. The results show that the warm extracts of C. officinalis, L. indica and P. granatum may be effective to prevent dental caries. In particular, the ethanol-based extracts of C. officinalis, P. suffruticosa and C. sinensis were effective to prevent dental caries and thus may be highly marketable. Chrysanthemum zawadskii, R. hybrida, P. granatum, C. japonica L. and Zinnia elegans showed high antibacterial activity against P.gingivalis. R. hybrida showed the highest ethanol extract activity, followed by P. suffruticosa, P. granatum, C. japonica L. and L. indica. R. hybrida, P. granatum, C. morifolium and C. japonica showed high activity against Pr.intermedia in the order named. C. zawadskii, P. granatum, L. indica, C. japonica and A. princeps showed high ethanol extract activity. Thus, the warm extracts of R. hybrida, P. granatum and C. japonica may be helpful to reduce halitosis. In addition, the ethanol-based extracts of P. granatum, C. japonica and L. indica are expected to be highly marketable as mouthwashes.

• Journal of Microbiology and Biotechnology
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• v.7 no.6
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• pp.391-396
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• 1997

Two series of carbon sources, linear primary $C_1$~$C_9$ alcohols and linear $C_2$~$C_{10}$ monocarboxylic acids were tested for PHA synthesis in Paracoccus denitrificans. The results showed that the growth-associated synthesis of PHA could be referred only to the carbon sources with odd number of carbon except methanol. For all carbon sources with even number of carbon, nitrogen limitation was required to induce PHA synthesis in P. denitrificans. Poly(3-hydroxyvalerate)[P(3HV)] homopolymer was synthesized from $C_5$, $C_7$, and $C_9$ while growing in the presence of nitrogen, but the nitrogen depletion in the later growth period incorporated 3-hydroxybutyrate(3HB) unit into the polymer chain. The optimum C/N ratio for P(3HV) homopolymer production was found to be 10 when the strain was grown on 10 ml/l of valeric acid for 96 h. P. denitrificans synthesized P(3HB-co-3HV) copolymers from n-hexanoic and n-octanoic acid. The microstructural characterics of the P(3HB-co-3HV) copolymer from n-propanol was investigated using $^13C$-nuclear magnetic resonance spectroscopy, showing a structural heterogeneity.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.5
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• pp.447-453
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• 2013

Osteoblastic activity of nectandrin A was examined in C2C12 cells. Nectandrin A enhances the BMP-induced osteoblastic differentiation and mineralization, manifested by the up-regulation of differentiation markers (alkaline phosphatase and osteogenic genes) and increased calcium contents. In C2C12 cells co-transfected with expression vector encoding Smad4 and Id1-Luc reporter, nectandrin A increased Id1 luciferase activity in a concentration-dependent manner, when compared to that in BMP-2 treated cells, indicating that Smad signaling pathway is associated with nectandrin A-enhanced osteoblastic differentiation in C2C12 cells. In addition, nectandrin A activated p38 mitogen-activated protein kinase (MAPK) in time- and concentration-dependent manners, and phosphorylated form of pSmad1/5/8 and alkaline phosphatase activity were both decreased when the cells were pretreated with SB203580, a p38 MAPK inhibitor, suggesting that p38 MAPK might be an upstream kinase for Smad signaling pathway. Taken together, nectandrin A enhances the BMP-induced osteoblastic differentiation and mineralization of C2C12 cells via activation of p38 MAPK-Smad signaling pathway, and it has a therapeutic potential for osteoporosis by promoting bone formation.

• Transactions of Materials Processing
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• v.3 no.4
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• pp.427-439
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• 1994

The high temperature deformation behavior of $SiC_p/Al-Si$ composites and Al-Si matrix was studied by hot torsion test in a range of temperature from $270^{\circ}C$ to $520^{\circ}C$ and at strain rate range of $1.2{\times}10_{-3}~2.16{\times}10_{-1}/sec$. The hot restoration mechanisms for both matrix and composites were found to be dynamic recrystallization(DRX) from the investigation of flow curves and microstructural evolutions. The Si precipitates and SiC particles promoted DRX, and the peak strain$({\varepsilon}_p)$ of the composites was smaller than that of the matrix. Flow stresses of $SiC_p/Al-Si$ composites were found to be generally higher than the matrix, but the difference was quite small at higher temperature due to the decrease of capability of load transfer by SiC particles. With increasing temperature, failure strain of matrix and composites are inclined to increase, the increasing value of failure strain for the $SiC_p/Al-Si$ composites was small compared to that of matrix. The stress dependence of both materials on strain rate() and temperature(T) was examined by hyperbolic sine law, $\.{\varepsilon}=A_1[sinh({\alpha}{\cdot}{\sigma})]_n$exp(-Q/RT)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.348-349
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• 2007

This paper describes the electrical characteristics of polycrystalline (poly) 3C-SiC thin film diodes, in which poly 3C-SiC thin films on n-type and p-type Si wafers, respectively, were deposited by APCVD using HMDS, Hz, and Ar gas at $1180^{\circ}C$ for 3 hr. The schottky diode with Au/poly 3C-SiC/Si(n-type) structure was fabricated. Its threshold voltage ($V_d$), breakdown voltage, thickness of depletion layer, and doping concentration ($N_D$) values were measured as 0.84 V, over 140 V, 61nm, and $2.7\;{\times}\;10^{19}\;cm^3$, respectively. The p-n junction diodes fabricated on the poly 3C-SiC/Si(p-type) were obtained like characteristics of single 3C-SiC p-n junction diodes. Therefore, poly 3C-SiC thin film diodes will be suitable microsensors in conjunction with Si fabrication technology.

• Korean Journal of Microbiology
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• v.29 no.3
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• pp.149-154
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• 1991

Escherichia coli/Corynebacterium glutamicum shuttle vectors, pECCG1 and pECCG2 were constructed by joining a 3.00 kb cryptic plasmid pCB 1 from C. glutamicum and a 3.94 kb plasmid pACYC 177 from E. coli. By trimming unessential parts and introducing mulitiple cloning site into the plasmid pECCG 1, a plasmid pECCG122(5.1kb) was constructed. All the shuttle vectors were stably maintained in C. glutamicum up to about 40 generations irrespective of kanamycin addition in the medium. Threonine operon (homoserine dehydrogenase/homoserine kinase) and dapA gene (dihydrodipicolinate synthetase) of C. glutamicum were cloned into the plasmid pECCG122, and the resultant plasmids were designated pTN31 and pDHDP19, respectively. They were used to study the effect of cloned foreign gene on the stability of the plasmid pECCG122. Plasmids pTN31 and pDHDP19 were segregated rapidly from C. glutamicum when cultured in the medium without kanamycin. In medium with $50\mu${\g/ml} of kanamycin, their segregation rates were much slower than those in medium without kanamycin, but the danamycin addition didn't guarantee the complete maintenance of the plasmids in C. glutamicum.

• Biomolecules & Therapeutics
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• v.29 no.2
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• pp.195-204
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• 2021

Cereblon (CRBN), a substrate receptor of cullin 4-RING E3 ligase (CRL4) regulates the ubiquitination and degradation of c-Jun, mediating the lipopolysaccharide-induced cellular response. However, the upstream signaling pathway that regulates this process is unknown. In this study, we describe how endoplasmic reticulum (ER) stress reversely regulates sequestosome-1 (p62)and c-Jun protein levels. Furthermore, our study reveals that expression of p62 attenuates c-Jun protein levels through the ubiquitinproteasome system. Conversely, siRNA knockdown of p62 elevates c-Jun protein levels. Immunoprecipitation and immunoblotting experiments demonstrate that p62 interacts with c-Jun and CRBN to form a ternary protein complex. Moreover, we find that CRBN knockdown completely abolishes the inhibitory effect of p62 on c-Jun. Using brefeldin A as an inducer of ER stress, we demonstrate that the p62/c-Jun axis participates in the regulation of ER stress-induced apoptosis, and that CRBN is required for this regulation. In summary, we have identified an upstream signaling pathway, which regulates p62-mediated c-Jun degradation. Our findings elucidate the underlying molecular mechanism by which p62/c-Jun axis regulates the ER stress-induced apoptosis, and provide a new molecular connection between ER stress and apoptosis.