• Title/Summary/Keyword: S-acts

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CONSTRUCTIVE PROOF FOR THE POSITIVITY OF THE ORBIT POLYNOMIAL On,2d(q)

  • Lee, Jaejin
    • Korean Journal of Mathematics
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    • v.25 no.3
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    • pp.349-358
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    • 2017
  • The cyclic group $C_n={\langle}(12{\cdots}n){\rangle}$ acts on the set $(^{[n]}_k)$ of all k-subsets of [n]. In this action of $C_n$ the number of orbits of size d, for d | n, is $$O^{n,k}_d={\frac{1}{d}}{\sum\limits_{{\frac{n}{d}}{\mid}s{\mid}n}}{\mu}({\frac{ds}{n}})(^{n/s}_{k/s})$$. Stanton and White [6] generalized the above identity to construct the orbit polynomials $$O^{n,k}_d(q)={\frac{1}{[d]_{q^{n/d}}}}{\sum\limits_{{\frac{n}{d}}{\mid}s{\mid}n}}{\mu}({\frac{ds}{n}})[^{n/s}_{k/s}]_{q^s}$$ and conjectured that $O^{n,k}_d(q)$ have non-negative coefficients. In this paper we give a constructive proof for the positivity of coefficients of the orbit polynomial $O^{n,2}_d(q)$.

How the Geometries of Newton's Flat and Einstein's Curved Space-Time Explain the Laws of Motion

  • Yang, Kyoung-Eun
    • Journal for History of Mathematics
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    • v.32 no.1
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    • pp.17-25
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    • 2019
  • This essay elucidates the way the geometries of space-time theories explain material bodies' motions. A conventional attempt to interpret the way that space-time geometry explains is to consider the geometrical structure of space-time as involving a causally efficient entity that directs material bodies to follow their trajectories corresponding to the laws of motion. Newtonian substantival space is interpreted as an entity that acts but is not acted on by the motions of material bodies. And Einstein's curved space-time is interpreted as an entity that causes the motions of bodies. This essay argues against this line of thought and provides an alternative understanding of the way space-time geometry explain the laws of motion. The workings of the way that Newton's flat and Einstein's curved space-time explains the law of motion is such that space-time geometry encodes the principle of inertia which specifies straight lines of moving bodies.

Control of Tylosin Biosynthesis in Streptomyces fradiae

  • Cundliffe, Eric
    • Journal of Microbiology and Biotechnology
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    • v.18 no.9
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    • pp.1485-1491
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    • 2008
  • Tylosin biosynthesis is controlled in cascade fashion by multiple transcriptional regulators, acting positively or negatively, in conjunction with a signalling ligand that acts as a classical inducer. The roles of regulatory gene products have been characterized by a combination of gene expression analysis and fermentation studies, using engineered strains of S. fradiae in which specific genes were inactivated or overexpressed. Among various novel features of the regulatory model, involvement of the signalling ligand is not essential for tylosin biosynthesis.

HEXAVALENT NORMAL EDGE-TRANSITIVE CAYLEY GRAPHS OF ORDER A PRODUCT OF THREE PRIMES

  • GHORBANI, MODJTABA;SONGHORI, MAHIN
    • Journal of applied mathematics & informatics
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    • v.35 no.1_2
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    • pp.83-93
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    • 2017
  • The Cayley graph ${\Gamma}=Cay(G,S)$ is called normal edge-transitive if $N_A(R(G))$ acts transitively on the set of edges of ${\Gamma}$, where $A=Aut({\Gamma})$ and R(G) is the regular subgroup of A. In this paper, we determine all hexavalent normal edge-transitive Cayley graphs on groups of order pqr, where p > q > r > 2 are prime numbers.

EQUIARIANT K-GROUPS OF SPHERES WITH INVOLUTIONS

  • Cho, Jin-Hwan;Mikiya Masuda
    • Journal of the Korean Mathematical Society
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    • v.37 no.4
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    • pp.645-655
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    • 2000
  • We calculate the R(G)-algebra structure on the reduced equivariant K-groups of two-dimensional spheres on which a compact Lie group G acts as a reflection. In particular, the reduced equivariant K-groups are trivial if G is abelian, which shows that the previous Y. Yang's calculation in [8] is incorrect.

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Fabrication and Investigation of Composite Made of Graphite, SiC, Mullite and Aluminum

  • Motaman, A.;Amin, S.A.;Jahangir, A.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09b
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    • pp.1071-1074
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    • 2006
  • Fabrication and investigation of composite made of graphite, SiC, mullite and aluminum as the additive are the aim of this project. Aluminum acts as an anti-oxidant. SiC is a non-metallic anti-oxidant that increases composite strength. Different compositions with influent percents of aluminum have been selected to determine product specifications by XRD, SEM and STA methods. Results show that the composition of 40wt% graphite-20% SiC- 20% mullite-20% aluminum is a more robust and occurs at elevated temperatures than other graphite combustion composites.

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Nonlinearlity Compensation of Heterodyne laser interferometer based on LMS (LMS를 이용한 헤테로다인 레이저 간섭계 비선형성 보정)

  • Jeong, Pil-Joong;Lee, Woo-Ram;You, Kwan-Ho
    • Proceedings of the KIEE Conference
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    • 2007.10a
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    • pp.283-284
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    • 2007
  • In this paper we introduce a compensation of nonlinearity Heterodyne laser interferometer. The Laser Interferometer is used for length measurement in various industries. However, it has nonlinearity error caused by the imperfect optical equipment. This acts as an obstacle in the measurement improvement. We propose an adaptive error compensation using least mean square(LMS) to improve precision.

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Lasiodiplodia theobromae is a Mycoparasite of a Powdery Mildew Pathogen

  • Kumar, P. Sreerama;Singh, Leena
    • Mycobiology
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    • v.37 no.4
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    • pp.308-309
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    • 2009
  • Powdery mildews on over 40 plants in Bangalore were screened during July-December of 2003~2008. Isolates from mycoparasitised Oidium caesalpiniacearum of Bauhinia purpurea comprised Lasiodiplodia theobromae, in addition to Ampelomyces quisqualis. Koch's postulates were satisfied to establish the mycoparasitism of L. theobromae. This is the first report that L. theobromae acts as a mycoparasite of a powdery mildew.

Involvement of Phosphodiesterase Isozymes in Osteoclast Formation

  • Yim, Mi-Jung
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.207.2-207.2
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    • 2003
  • cAMP acts as a second messenger in the functional responses of various cells to hormones, cytokines and other agents. In turn, this nucleotide also modulates the signal transduction processes regulated by a range of cytokines and growth factors. The intracellular level of cAMP is regulated by a G protein coupled adenylyl cyclase and degradation is mediated by the phosphodiesterases (PDEs), a superfamily of enzymes that catalyze the hydrolysis of cAMP. (omitted)

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Expected Roles of the Korean Institutional Investors for listed S&M sized firms in the KSE (상장중소기업의 직접금융 활성화를 위한 기관투자가 역할)

  • Jun, Yang-jin
    • Journal of the Korean Society of Industry Convergence
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    • v.7 no.4
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    • pp.363-368
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    • 2004
  • The stocks of listed S&M sized firms in the KoreaStock Exchange(KSE) have been neglected to investors for long time in site of their good performences. The word "Neglected" means that the stocks of listed S&M sized firms in the KSE have fail to acquried liquidity. In the result, Listed S&M sized firms in the KSE have not financed equity by issuing stocks timely in the primary market. This problem has resulted in poor investment to their listed S&M sized firms in the KSE. The possible key to sovlve this problem is in the Institutional Investors, especially to the Pension fund. Korean Institutional Investors have lost their basic roles, that is, final supports to prevent the markets not to demolish. The Acts prventing Pension to invest to the stocks is to change to allowing to invest them in soon. this opportunity is good chance to solve the problems of poor liquidity of stocks of listed S&M sized firms in the KSE.

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