• Title/Summary/Keyword: f-modules

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GLn- DECOMPOSITION OF THE SCHUR COMPLEX Sr2 φ)

  • Choi, Eun J.;Kim, Young H.;Ko, Hyoung J.;Won, Seoung J.
    • Bulletin of the Korean Mathematical Society
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    • v.40 no.1
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    • pp.29-51
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    • 2003
  • In this paper we construct a natural filtration associated to the plethysm $S_{r}(\wedge^2 \varphi)$ over arbitrary commutative ring R. Let $\phi$ : G longrightarrow F be a morphism of finite free R-modules. We construct the natural filtration of $S_{r}(\wedge^2 \varphi)$ as a $GL(F){\times}GL(G)$- complex such that its associated graded complex is ${\Sigma}_{{\lambda}{\in}{\Omega}_{\gamma}}=L_{2{\lambda}{\varphi}$, where ${{\Omega}_{\gamma}}^{-}$ is a set of partitions such that $│\wedge│\;=;{\gamma}\;and\;2{\wedge}$ is a partition of which i-th term is $2{\wedge}_{i}$. Specializing our result, we obtain the filtrations of $S_{r}(\wedge^2 F)\;and\;D_{r}(D_2G).

NATURAL FILTRATIONS OF SOME PLETHYSMS

  • Kim, Young-Hie;Ko, Hyoung J.;Lee, Kyung-Ae
    • Bulletin of the Korean Mathematical Society
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    • v.37 no.1
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    • pp.191-207
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    • 2000
  • Let R be a ommutative ring with unity and F a finite free R-module. For a nonnegative integer r, there exists a natural filtration of$S_r(S_2F)$ such that its associated graded module is isomorphic to $\Sigma_{{\lambda}{\epsilon}{\tau}_r}\;L_{\lambda}F$, where ${\Gamma}_{\gamma}$ set of partitions such that $$\mid${\lambda}$\mid$-2r,{{\widetilde}{\lambda}}-{{\widetilde}{\lambda}}_1},...,{{\widetilde}{\lambda}}_k},\;each\;{{\widetilde}{\lambda}}_t}$,is even. We call such filtrations plethysm formulas. We extend the above plethysm formula to the version of chain complexes. By plethysm formula we mean the composition of universally free functors. $Let{\emptyset}:G->F$ be a morphism of finite free R-modules. We construct the natural decomposition of $S_{r}(S_2{\emptyset})$,up to filtrations, whose associated graded complex is isomorphic to ${\Sigma}_{{\lambda}{\varepsilon}{\tau}}_r}\;L_{\lambda}{\emptyset}$.

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A GENERALIZATION OF THE ZERO-DIVISOR GRAPH FOR MODULES

  • Safaeeyan, Saeed;Baziar, Mohammad;Momtahan, Ehsan
    • Journal of the Korean Mathematical Society
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    • v.51 no.1
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    • pp.87-98
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    • 2014
  • Let R be a commutative ring with identity and M an R-module. In this paper, we associate a graph to M, say ${\Gamma}(M)$, such that when M = R, ${\Gamma}(M)$ is exactly the classic zero-divisor graph. Many well-known results by D. F. Anderson and P. S. Livingston, in [5], and by D. F. Anderson and S. B. Mulay, in [6], have been generalized for ${\Gamma}(M)$ in the present article. We show that ${\Gamma}(M)$ is connected with $diam({\Gamma}(M)){\leq}3$. We also show that for a reduced module M with $Z(M)^*{\neq}M{\backslash}\{0\}$, $gr({\Gamma}(M))={\infty}$ if and only if ${\Gamma}(M)$ is a star graph. Furthermore, we show that for a finitely generated semisimple R-module M such that its homogeneous components are simple, $x,y{\in}M{\backslash}\{0\}$ are adjacent if and only if $xR{\cap}yR=(0)$. Among other things, it is also observed that ${\Gamma}(M)={\emptyset}$ if and only if M is uniform, ann(M) is a radical ideal, and $Z(M)^*{\neq}M{\backslash}\{0\}$, if and only if ann(M) is prime and $Z(M)^*{\neq}M{\backslash}\{0\}$.

Expression and Characterization of Trehalose Biosynthetic Modules in the Adjacent Locus of the Salbostatin Gene Cluster

  • Choeng, Yong-Hoon;Yang, Ji-Yeon;Delcroix, Gaetan;Kim, Yoon-Jung;Chang, Yong-Keun;Hong, Soon-Kwang
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1675-1681
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    • 2007
  • The pseudodisaccharide salbostatin, which consists of valienamine linked to 2-amino-1,5-anhydro-2-deoxyglucitol, is a strong trehalase inhibitor. From our Streptomyces albus ATCC 21838 genomic library, we identified thirty-two ORFs in a 37-kb gene cluster. Twenty-one genes are supposed to be a complete set of modules responsible for the salbostatin biosynthesis. Through sequence analysis of the gene cluster, some of the upstream gene products (SalB, SalC, SalD, SalE, and SalF) revealed functional resemblance with trehalose biosynthetic enzymes. On the basis of this rationale, we isolated the five genes (salB, salC, salD, salE, and salF) from the S. albus ATCC 21838 and cloned them into the expression vector pWHM3. We demonstrated the noticeable expression and accumulation of trehalose, using only the five upstream biosynthetic gene cluster of salbostatin, in the transformed Streptomyces lividans TK24. Finally, 490 mg/l trehalose was produced by fermentation of the transformant with sucrosedepleted R2YE media.

Data-driven SIRMs-connected FIS for prediction of external tendon stress

  • Lau, See Hung;Ng, Chee Khoon;Tay, Kai Meng
    • Computers and Concrete
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    • v.15 no.1
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    • pp.55-71
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    • 2015
  • This paper presents a novel harmony search (HS)-based data-driven single input rule modules (SIRMs)-connected fuzzy inference system (FIS) for the prediction of stress in externally prestressed tendon. The proposed method attempts to extract causal relationship of a system from an input-output pairs of data even without knowing the complete physical knowledge of the system. The monotonicity property is then exploited as an additional qualitative information to obtain a meaningful SIRMs-connected FIS model. This method is then validated using results from test data of the literature. Several parameters, such as initial tendon depth to beam ratio; deviators spacing to the initial tendon depth ratio; and distance of a concentrated load from the nearest support to the effective beam span are considered. A computer simulation for estimating the stress increase in externally prestressed tendon, ${\Delta}f_{ps}$, is then reported. The contributions of this paper is two folds; (i) it contributes towards a new monotonicity-preserving data-driven FIS model in fuzzy modeling and (ii) it provides a novel solution for estimating the ${\Delta}f_{ps}$ even without a complete physical knowledge of unbonded tendons.

Control of Input Series Output Parallel Connected DC-DC Converters

  • Natarajan, Sirukarumbur Pandurangan;Anandhi, Thangavel Saroja
    • Journal of Power Electronics
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    • v.7 no.3
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    • pp.265-270
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    • 2007
  • Equal rating DC-DC converter modules can be connected in series at the input for circuits requiring higher input voltages and in parallel at the output for circuits requiring higher output currents. Since the converter modules may not be practically identical, closed loop control has to ensure that each module equally shares the total input voltage and the load current. A control scheme consisting of a common output voltage loop, individual inner current loops and individual input voltage loops have been designed in this work to achieve input voltage and load current sharing as well as load voltage regulation under supply and load disturbances. The output voltage loop provides the basic reference for the inner current loops, which are also modified by the respective input voltage loops. The average of the converter input voltages, which is dynamically varying, is chosen as the reference for input voltage loops. This choice of reference eliminates interaction among different control loops. Type II compensators and Fuzzy Logic Controllers (FLCs) are designed and compared through MATLAB based simulation and FLC is found to be satisfactory. Hence TMS320F2407A DSP based FLC is implemented and the results are presented which prove the superiority of the FLC developed for this research.

Cutting Force Test of Cutting Blade Modules for Slitter Design

  • Kim, Young-Hwan;Cho, Yung-Zun;Lee, Young-Soon
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2017.10a
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    • pp.189-190
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    • 2017
  • For the concept design of the device, a tool was made to test the simulated fuel rods and cutting force and the cutting force was measured. When 2-CUT and 3-CUT modules were used, the maximum force in 2-CUT at 12.5 mm/s speed change was $197.5kg_f$ and the maximum force at 3-CUT was $363.2kg_f$. The change of force in 2-CUT rapidly increases from about 1 second, and you can see that there are increase and decrease of the force change from about 5 seconds to 18 seconds, and it was rapidly decreased and the cut was made. The force change in 3-CUT has higher force at about 5 seconds later than 2-CUT at the speed of 12.5 mm/s, and you can see that it has the same tendency afterwards. If you search for the force at adequate speed from this cutting force test, 2-CUT module requires less slitting force than 3-CUT module, and the cutting time for 250 mm at 12.5 mm/s was 21 seconds, which can cut 4 m fuel rod in 5 minutes. But, there are cases of not completely slitting with 2-CUT module, so it is necessary to supplement this in the future through experiments.

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