• Journal of Power Electronics
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• v.10 no.1
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• pp.97-105
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• 2010

This paper presents the modeling, control and simulation of an interconnection system (ICS) of cascaded distributed generation (DG) modules for both grid-tied and stand-alone operations. The overall configuration of the interconnection system is given. The interconnection system consists of a cascaded DC/DC boost converters and a DC/AC inverter. Detailed modeling of the interconnection system incorporating a cascaded architecture has not been considered in previous research. In this paper, suitable control systems for the cascaded architecture of power electronic converters in an interconnection system have been studied and modeled in detail. A novel control system for DC/DC boost converters is presented based on a droop voltage controller. Also, a novel control strategy for DC/AC inverters based on the average large signal model to control the aggregated DG modules under both grid-tied and stand-alone modes is demonstrated. Simulation results indicate the effectiveness of the proposed control systems.

• Communications of the Korean Mathematical Society
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• v.38 no.3
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• pp.733-740
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• 2023

Let R be a commutative ring and M be an R-module. The dimension graph of M, denoted by DG(M), is a simple undirected graph whose vertex set is Z(M) ⧵ Ann(M) and two distinct vertices x and y are adjacent if and only if dim M/(x, y)M = min{dim M/xM, dim M/yM}. It is shown that DG(M) is a disconnected graph if and only if (i) Ass(M) = {𝖕, 𝖖}, Z(M) = 𝖕 ∪ 𝖖 and Ann(M) = 𝖕 ∩ 𝖖. (ii) dim M = dim R/𝖕 = dim R/𝖖. (iii) dim M/xM = dim M for all x ∈ Z(M) ⧵ Ann(M). Furthermore, it is shown that diam(DG(M)) ≤ 2 and gr(DG(M)) = 3, whenever M is Noetherian with |Z(M) ⧵ Ann(M)| ≥ 3 and DG(M) is a connected graph.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.2
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• pp.166-177
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• 1997

The prime mover performance of on - board Diesel Generator is well characterized by the variation of frequency and the load sharing on parallel running under electric load change. This study is aimed to configure the modeling for performance simulation regarding to DG operation which could be interested for education purpose or system analysis. The modeling had been made on the base of modules such as govenor, prime mover of diesel engine and generator with electric load system, which were then intergrated for total simula¬tion performance. One real model system has been introduced for deciding relating parameters and for the comparison of resulting performance in simulation. The responses from the modelling were confirmed in single and paralell operation, the results of which showed resonable accordance with the real system.

• Bulletin of the Korean Mathematical Society
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• v.54 no.5
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• pp.1803-1825
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• 2017

Let X be a smooth scheme with an action of an algebraic group G. We establish an equivalence of two categories related to the corresponding moment map ${\mu}:T^{\ast}X{\rightarrow}g^{\ast}$ - the derived category of G-equivariant coherent sheaves on the derived fiber ${\mu}^{-1}(0)$ and the derived category of G-equivariant matrix factorizations on $T^{\ast}X{\times}g$ with potential given by ${\mu}$.

• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1525-1535
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• 2014

The xynC gene, which encodes high molecular weight xylanase from Paenibacillus sp. DG-22, was cloned and expressed in Escherichia coli, and its nucleotide sequence was determined. The xynC gene comprised a 4,419bp open reading frame encoding 1,472 amino acid residues, including a 27 amino acid signal sequence. Sequence analysis indicated that XynC is a multidomain enzyme composed of two family 4_9 carbohydrate-binding modules (CBMs), a catalytic domain of family 10 glycosyl hydrolases, a family 9 CBM, and three S-layer homologous domains. Recombinant XynC was purified to homogeneity by heat treatment, followed by Avicel affinity chromatography. SDS-PAGE and zymogram analysis of the purified enzyme identified three active truncated xylanase species. Protein sequencing of these truncated proteins showed that all had identical N-terminal sequences. In the protein characterization, recombinant XynC exhibited optimal activity at pH 6.5 and $65^{\circ}C$ and remained stable at neutral to alkaline pH (pH 6.0-10.0). The xylanase activity of recombinant XynC was strongly inhibited by 1 mM $Cu^{2+}$ and $Hg^{2+}$, whereas it was noticeably enhanced by 10 mM dithiothreitol. The enzyme exhibited strong activity towards xylans, including beechwood xylan and arabinoxylan, whereas it showed no cellulase activity. The hydrolyzed product patterns of birchwood xylan and xylooligosaccharides by thin-layer chromatography confirmed XynC as an endoxylanase.