• Korean Journal of Microbiology
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• v.25 no.1
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• pp.40-45
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• 1987

The gene for the Bdi I modification enzyme, which is one of Bdi I restriction-modification system, fromBrevibacterium divaricatum FERM 5948 was cloned and expressed in E. coli. For cloning of the Bdi I methylase gene, we have initially used three cloning site(EcoRI, BamHI and Sal I) of plasmid vector pBR 322 and adopted the retransformation method after Bdi I restriction endonuclease cleavage. Selection of transformants carrying the gene was based on the resistance of the modified plasmid encoding the enzyme to cleavage by Bdi I restriction enzyme, and the recombinant plasmid pBDIM 116 containing 5.6kb EcoRI insery was proved to carry the gene. Crude cell extracts prepared from strains carrying the plasmid pBDIM 116 contained an S-adenosylmethionine-dependent methyltransferase activity specific for the Bdi I recognition site, ATCGAT. The restriction map was constructed with 11 restriction enzyme, and the Bdi I restriction-modification system was also discussed.

• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.123-127
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• 1996

The isolation and chemical characterization of yellow food pigments from Monascus purpureus were studied according to the compositions of media. Monacus yellow pigments were isolated and purified by solvent fractionation, silicagel column chromatography, TLC and HPLC. The retention time of Monascus yellow pigments isolated by HPLC was respectively 5 min(I) and 9 min(II) as the yeast malt extract agar(YMA) media and was respectively 4.6 min(III), 5 min(I) 5.7 min(IV), 8.3 min(V), 9 min(II) and 10.7 min(Ⅵ) at the malt extract agar(MEA) media. The structure of monascin(I), ankaflavin(II), 6,11-dihydrorubropunctatin(III), 6,11-dihydromonascorubrin(V) and unknown compounds(IV,Ⅵ) was elucidated by EI-Mass, H and C NMR, UV-visible spectrometer. Therefore, it was suggested that 6,11-dihydrorubropunctatin(III) and 6,11-dihydromonascorubrin(V) are new intermediates of Monascus yellow pigments.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.295-297
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• 2004

무선랜에 대한 사용과 응용이 늘어나면서 등장한 요구사항들을 충족시키기 위하여 IEEE 802.11에 새로운 규격들이 계속하여 추가되고 있다. 그중 802.11i와 802.11f는 각각 무선랜 보안 강화와 액세스포인트 사이의 정보 교환을 목적으로 제정되었다. 802.11i에 의한 보안기능 강화로 인하여 스테이션의 로밍 과정에서의 지연 시간이 길어지게 되었고 이를 해결하기 위한 선인증 방식이 사용될 수 있다. 그러나 802.11i선인증 방식에서는 스테이션이 로밍하여 갈 액세스포인트를 미리 예상하고 인증을 받아야 한다는 단점이 있다 본 논문에서는 IAPP 프로토콜을 사용하여 액세스포인트 사이에 인증 정보를 교환함으로써 스테이션이 관여하지 않고 선인증을 수행하는 방법을 제안하고, 802.11i 선인증 방식에 대한 장단점을 비교한다.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.6
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• pp.1515-1523
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• 2015

It has been prevalent to be serviced through WLAN(Wireless Local Area Network) as a variety of mobile devices have been introduced. If the number of mobile devices increases rapidly for the network access in a limited range of ESS(Extended Service Set), a lengthy connection delays are induced due to the initial link setup process of the IEEE 802.11i which is WLAN security standard. In this paper, we propose a new initial link setup protocol which can be executed in the ESS area of WLAN.

• Journal of Institute of Control, Robotics and Systems
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• v.11 no.11
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• pp.895-900
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• 2005

We derive a linear matrix inequality(LMI) condition guaranteeing that any invariant zeros of a triple (A, B, C) lie in the open left half plane of the complex plane, i.e. $C(sI-A)^{-1}B$ is minimum phase. The LMI condition is equivalent to a certain constrained Lyapunov matrix equation which can be found in many results relating to stability analysis or control design. We show that the LMI condition can be used to simplify various control engineering problems such as a dynamic output feedback control problem, a variable structure static output feedback control problem, and a nonlinear system observer design problem. Finally, we give some numerical examples.

• Animal Systematics, Evolution and Diversity
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• v.6 no.2
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• pp.193-208
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• 1990

Ianiropsis material collected from 11 localities of the Korean coasts were studied . Six species including one new species were identified to be new to Korea ; Ianiropsis derjugini Gurjanova, I.setifera Gurjanova, I. epilittoralis Menzies , I. tridens Menzies, I. serricaudis Gurjanova and I.koreaensis n.sp. All species are described and figured with a key to the Korean species of the Ianiropsis.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.2
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• pp.176-179
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• 2003

Insulin-like growth factor-I (IGF-I) is a polypeptide that has the function of regulating the expression of steroid hormones through endocrine, paracrine, and autocrine actions in reproductive organs. Moreover, IGF-I is involved in ovulation, implantation, maintenance of pregnancy, and development of fetuses in animals. Therefore, this study was conducted to investigate the effects of serum IGF-I concentration on progesterone ($P_4$) concentration and pregnancy rates in Korean native cattle (Hanwoo). Blood was collected at estrus (Day 0) and Day 11. Artificial insemination was performed at Day 0. Serum IGF-I and $P_4$ concentrations were measured by radioimmunoassay (RIA). Overall, $P_4$ concentration was higher at Day 11 than Day 0, whereas the pattern of IGF-I concentration was reversed. When animals were divided into two groups depending on the pregnancy status, $P_4$ concentrations of the pregnant group was significantly higher than that of the non-pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05). But, lower IGF-I concentrations were detected in the pregnant group at Day 0 (p<0.05) and Day 11 (p<0.05) compared to the non-pregnant group. In conclusion, these results indicated that serum IGF-I is inversely associated with $P_4$ concentration during early pregnancy in Hanwoo.

• Bulletin of the Korean Chemical Society
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• v.25 no.11
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• pp.1631-1632
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• 2004

• IMMUNE NETWORK
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• v.11 no.4
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• pp.223-226
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• 2011

Although exercise-induced growth factors such as Insulin-like growth factor-I (IGF-I) are known to affect various aspects of physiology in skeletal muscle cells, the molecular mechanism by which IGF-I modulates anti-inflammatory effects in these cells is presently unknown. Here, we showed that IGF-I stimulation suppresses the expression of toll-like receptor 4 (TLR4), a key innate immune receptor. A pharmacological inhibitor study further showed that PI3K/Akt signaling pathway is required for IGF-I-mediated negative regulation of TLR4 expression. Furthermore, IGF-I treatment reduced the expression of various NF-${\kappa}B$-target genes such as TNF-${\alpha}$ and IL-6. Taken together, these findings indicate that the anti-inflammatory effect of exercise may be due, at least in part, to IGF-I-induced suppression of TLR4 and subsequent downregulation of the TLR4-dependent inflammatory signaling pathway.

• International journal of advanced smart convergence
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• v.11 no.2
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• pp.1-6
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• 2022

With the emergence of the new era of the 4th industrial revolution, compute-bound workloads with large memory footprint like big data processing increase dramatically. Even in such compute-bound workloads, however, we observe bulky I/Os while loading big data from storage to memory. Although file I/O cache plays a role of accelerating the performance of storage I/O, we found out that the cache hit rate in such environments is not improved even though we increase the file I/O cache capacity because of some special I/O references generated by compute-bound workloads. To cope with this situation, we propose a new file I/O cache management policy that improves the cache hit rate for compute-bound workloads significantly. Trace-driven simulations by replaying file I/O reference logs of compute-bound workloads show that the proposed cache management policy improves the cache hit rate compared to the well-acknowledged CLOCK algorithm by a large margin.