• The Journal of Information Systems
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• v.14 no.3
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• pp.9-16
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• 2005

In this paper, the performance of the WebService architecture for QoS guaranteed connection provisioning in inter-AS domain networks has been measured and analyzed for service publish/inquiry, collection of NMSs ASBR details, source routing by ingress NMS in constraint based routing and connection establishment. From the analysis, it has been found that, the connection between inter-AS domain networks can be established within the usual time limits of 3 seconds by the Web Service architecture. Since no standard solutions have been implemented in Interdomain QoS provisioning, this performance analysis assures Web Service architecture as a promising solution and can be easily implemented in the early stages of MPLS network employment.

• Macromolecular Research
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• v.14 no.3
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• pp.365-372
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• 2006

Poly[styrene-b-(ethylene-co-butylene)-b-styrene](SEBS) triblock copolymer was studied by dissolving the ethylene butylene midblock in selective hydrocarbon oils. These oils differ in their aromatic, paraffinic and naphthenic content. Dynamic rheological studies showed that the storage modulus (G') exceeded the loss modulus (G') for all the gels over the entire range of frequency, thereby confirming them as physical gels. However, the behavior of G' and G' as a function of frequency depended primarily on the oil type. The gelation melting temperature decreased drastically with increased oil aromaticity. Small angle X-ray scattering studies revealed that the maximum interdomain interference shifted to a higher angle depending on the composition and type of hydrocarbon oil.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.7
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• pp.141-148
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• 2001

This paper describes a mechanisms for IPv6 multihomming with loadsharing broker, focusing on the interdomain scalability and load sharing with redundancy on IPv6 networks. Unlike currently-practiced IPv4 multihoming, this model does not impact the worldwide routing table size, also it provides inbound load sharing at site level based on router renumbering, and multiple-prefix assigning techniques of IPv6. The proposed model has four modules such as building interfaces MIB module, priority list maintaining module, load detection module, and RRP configuration module.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.637-647
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• 2016

Proliferating cell nuclear antigen (PCNA) is a critical eukaryotic replication accessory factor that supports DNA binding in DNA processing, such as DNA replication, repair, and recombination. PCNA consists of three toroidal-shaped monomers that encircle double-stranded DNA. The diverse functions of PCNA may be regulated by its interactions with partner proteins. Many of the PCNA partner proteins generally have a conserved PCNA-interacting peptide (PIP) motif, located at the N- or C- terminal region. The PIP motif forms a 3₁₀ helix that enters into the hydrophobic groove produced by an interdomain-connecting loop, a central loop, and a C-terminal tail in the PCNA. Post-translational modification of PCNA also plays a critical role in regulation of its function and binding partner proteins. Structural and biochemical studies of PCNA-protein will be useful in designing therapeutic agents, as well as estimating the outcome of anticancer drug development. This review summarizes the characterization of eukaryotic PCNA in relation to the protein structures, functions, and modifications, and interaction with proteins.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7B
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• pp.711-721
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• 2004

To provide the end-to-end service differentiation for assured services, the random early demotion and promotion (REDP) marker in the edge router at each domain boundary monitors the aggregate flow of the incoming in-profile packets and demotes in-profile packets or promotes the previously demoted in-profile packets at the aggregate flow level according to the negotiated interdomain service level agreement (SLA). The REDP marker achieves UDP fairness in demoting and promoting packets through random and early marking decisions on packets. But, TCP fairness of the REDP marker is not obvious as fur UDP sources. In this paper, to improve TCP fairness of the REDP marker, we combine a dropper with the REDP marker. To make packet transmission rates of TCP flows more fair, at the aggregate flow level the combined dropper drops incoming excessive in-profile packets randomly with a constant probability when the token level in the leaky bucket stays In demotion region without incoming demoted in-profile packets. It performs a dropping in the demotion at a domain boundary only if there is no prior demotion. The concatenate dropping at multiple domains is avoided to manifest the effect of a dropping at a domain boundary on TCP fairness. We experiment with the REDP marker with the combined dropper using ns2 simulator for TCP sources. The simulation results show that the REDP marker with the combined dropper improves TCP fairness in demoting and promoting packets by generating fair demoted in-profile traffic compared to the REDP marker. The effectiveness of the selected drop probability is also investigated with showing its impact on the performance of the REDP marker with the combined dropper.

• Korean Journal of Microbiology
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• v.55 no.2
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• pp.123-130
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• 2019

Chelatase catalyzes the insertion of divalent metal into tetrapyrrole and plays a key role in the biosynthesis of metallated tetrapyrroles, such as cobalamin, siroheme, heme, and chlorophyll. SirB is a sirohydrochlorin (SHC) chelatase that generates cobalt-SHC or iron-SHC by inserting cobalt or iron into the center of sirohydrochlorin tetrapyrrole. To provide structural insights into the metal-binding and SHC-recognition mechanisms of SirB, we determined the crystal structure of SirB from Bacillus subtilis subsp. spizizenii (bssSirB) in complex with cobalt ions. bssSirB forms a monomeric ${\alpha}/{\beta}$ structure that consists of two domains, an N-terminal domain (NTD) and a C-terminal domain (CTD). The NTD and CTD of bssSirB adopt similar structures with a four-stranded ${\beta}-sheet$ that is decorated by ${\alpha}-helices$. bssSirB presents a highly conserved cavity that is generated between the NTD and CTD and interacts with a cobalt ion on top of the cavity using two histidine residues of the NTD. Moreover, our comparative structural analysis suggests that bssSirB would accommodate an SHC molecule into the interdomain cavity. Based on these structural findings, we propose that the cavity of bssSirB functions as the active site where cobalt insertion into SHC occurs.