• Title/Summary/Keyword: Alpha function

Search Result 1,705, Processing Time 0.027 seconds

THE FRACTIONAL TOTIENT FUNCTION AND STURMIAN DIRICHLET SERIES

  • Kwon, DoYong
    • Honam Mathematical Journal
    • /
    • v.39 no.2
    • /
    • pp.297-305
    • /
    • 2017
  • Let ${\alpha}$ > 0 be a real number and $(s_{\alpha}(n))_{n{\geq}1}$ be the lexicographically greatest Sturmian word of slope ${\alpha}$. We investigate Dirichlet series of the form ${\sum}^{\infty}_{n=1}s_{\alpha}(n)n^{-s}$. To do this, a generalization of Euler's totient function is required. For a real ${\alpha}$ > 0 and a positive integer n, an arithmetic function ${\varphi}{\alpha}(n)$ is defined to be the number of positive integers m for which gcd(m, n) = 1 and 0 < m/n < ${\alpha}$. Under a condition Re(s) > 1, this paper establishes an identity ${\sum}^{\infty}_{n=1}s_{\alpha}(n)n^{-S}=1+{\sum}^{\infty}_{n=1}{\varphi}_{\alpha}(n)({\zeta}(s)-{\zeta}(s,1+n^{-1}))n^{-s}$.

A GENERALIZATION OF SILVIA CLASS OF FUNCTIONS

  • Lee, Suk-Young;Oh, Myung-Sun
    • Communications of the Korean Mathematical Society
    • /
    • v.12 no.4
    • /
    • pp.881-893
    • /
    • 1997
  • E. M. Silvia introduced the class $S^\lambda_\alpha$ of $\alpha$-spirallike functions f(z) satisfying the condition $$ (A) Re[(e^{i\lambda} - \alpha) \frac{zf'(z)}{f(z)} + \alpha \frac{(zf'(z))'}{f'(z)}] > 0, $$ where $\alpha \geq 0, $\mid$\lambda$\mid$ < \frac{\pi}{2}$ and $$\mid$z$\mid$ < 1$. We will generalize Silvia class of functions by formally replacing f(z) in the denominator of (A) by a spirallike function g(z). We denote the new class of functions by $Y(\alpha,\lambda)$. In this note we obtain some results for the class $Y(\alpha,\lambda)$ including integral representation formula, relations between our class $Y(\alpha,\lambda)$ and Ziegler class $Z_\lambda$, the radius of convexity problem, a few coefficient estimates and a covering theorem for the class $Y(\alpha,\lambda)$.

  • PDF

AN INEQUALITY OF SUBHARMONIC FUNCTIONS

  • Choi, Chang-Sun
    • Journal of the Korean Mathematical Society
    • /
    • v.34 no.3
    • /
    • pp.543-551
    • /
    • 1997
  • We prove a norm inequality of the form $\left\$\mid$ \upsilon \right\$\mid$ \leq (r - 1) \left\$\mid$ u \right\$\mid$_p, 1 < p < \infty$, between a non-negative subharmonic function u and a smooth function $\upsilon$ satisfying $$\mid$\upsilon(0)$\mid$ \leq u(0), $\mid$\nabla\upsilon$\mid$ \leq \nabla u$\mid$$ and $\mid$\Delta\upsilon$\mid$ \leq \alpha\Delta u$, where $\alpha$ is a constant with $0 \leq \alpha \leq 1$. This inequality extends Burkholder's inequality where $\alpha = 1$.

  • PDF

ON SLIGHTLY $\alpha$-CONTINUOUS FUNCTIONS

  • Chae, G.I.;Noiri, T.;Kim, J.S.
    • East Asian mathematical journal
    • /
    • v.19 no.2
    • /
    • pp.241-249
    • /
    • 2003
  • In [11] the feeble continuity is introduced and then the weak and strong forms of feeble(or, equivalently $\alpha$-continuity) continuity are studied. In this note, we introduce a type of function called a slightly $\alpha$-continuous function and study several properties of it

  • PDF

A SINGULAR FUNCTION FROM STURMIAN CONTINUED FRACTIONS

  • Kwon, DoYong
    • Journal of the Korean Mathematical Society
    • /
    • v.56 no.4
    • /
    • pp.1049-1061
    • /
    • 2019
  • For ${\alpha}{\geq}1$, let $s_{\alpha}(n)={\lceil}{\alpha}n{\rceil}-{\lceil}{\alpha}(n-1){\rceil}$. A continued fraction $C({\alpha})=[0;s_{\alpha}(1),s_{\alpha}(2),{\ldots}]$ is considered and analyzed. Appealing to Diophantine approximation, we investigate the differentiability of $C({\alpha})$, and then show its singularity.

AREA OF TRIANGLE IN THE PLANE WITH ALPHA DISTANCE FUNCTION

  • Oh, Chae Hee;Ko, Il Seog;Kim, Byung Hak
    • The Pure and Applied Mathematics
    • /
    • v.19 no.4
    • /
    • pp.337-347
    • /
    • 2012
  • The taxicab distance and Chinese-checker distance in the plane are practical distance notions with a wide range of applications compared to the Euclidean distance. The ${\alpha}$-distance was introduced as a generalization of these two distance functions. In this paper, we study alpha circle, trigonometry, and the area of a triangle in the plane with ${\alpha}$-distance.

THE n-DIMENSIONAL SPα AND Mα-INTEGRALS

  • Park, Jae-Myung
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.15 no.2
    • /
    • pp.41-46
    • /
    • 2003
  • In this paper, we investigate the $SP_{\alpha}$-integral and the $M_{\alpha}$-integral defined on an interval of the n-dimensional Euclidean space $\mathbb{R}^n$. In particular, we show that these two integrals are equivalent.

  • PDF

Ric-8B Modulates the Function of Alpha Subunit of Go

  • Kim, Seung-Hyun;Ghil, Sung-Ho
    • Biomedical Science Letters
    • /
    • v.13 no.2
    • /
    • pp.127-133
    • /
    • 2007
  • Heterotrimeric GTP binding proteins (G proteins) mediate signal generated by neurotransmitter and hormones. Among all G proteins, Go is the most abundant in brain but its role in brain is not clearly understood. To determine the function of the alpha subunit of Go (Go$\alpha$), we search for the interacting partner of Go$\alpha$ in brain using yeast two-hybrid system. A resistant to inhibitor of cholinesterase (Ric-8B) was identified as a Go$\alpha$ interacting protein. We confirmed interaction between Go$\alpha$ and Ric-8b employing in vitro affinity binding assay and showed that the Ric-8b increased the function of Go$\alpha$. Our findings indicate that Ric-8b is possible guanine nucleotide exchange factor for Go$\alpha$.

  • PDF

Effect of Stilbenoids on TNF-${\alpha}$-induced Adipokine Secretion

  • Ahn, Ji-Yun;Lee, Hyun-Jung;Kim, Sun-A;Ha, Tae-Youl
    • Food Science and Biotechnology
    • /
    • v.18 no.5
    • /
    • pp.1284-1287
    • /
    • 2009
  • Tumor necrosis factor (TNF)-${\alpha}$ is chronically elevated in adipose tissues of obese rodents and humans. Increased levels of TNF-${\alpha}$ have been implicated in both the induction of atherogenic adipokines, such as plasminogen activator inhibitor (PAI)-1, and the inhibition of the anti-atherogenic adipokine, adiponectin. In this study, we investigated the effects of trans-stilbene, piceatannol, rhaponticin, and piceid on the TNF-${\alpha}$-induced atherogenic changes of adipokines in 3T3-L1 cells. Exposure to TNF-${\alpha}$ for 24 hr increased PAI-1 secretion and decreased adiponectin secretion. Among stilbenoids, piceatannol significantly inhibited the increased secretion of PAI-1 induced by TNF-${\alpha}$. Adiponectin secretion decreased by TNF-${\alpha}$ was recovered after trans-stilbene and rhaponticin treatments. Our results showed that stilbenoids exerted different effects on TNF-${\alpha}$-induced changes in adipokines secretion in 3T3-L1 adipocytes according to their structural characteristics.

SOME LOGARITHMICALLY COMPLETELY MONOTONIC FUNCTIONS RELATED TO THE GAMMA FUNCTION

  • Qi, Feng;Guo, Bai-Ni
    • Journal of the Korean Mathematical Society
    • /
    • v.47 no.6
    • /
    • pp.1283-1297
    • /
    • 2010
  • In this article, the logarithmically complete monotonicity of some functions such as $\frac{1}{[\Gamma(x+1)]^{1/x}$, $\frac{[\Gamma(x+1)]^{1/x}}{x^\alpha}$, $\frac{[\Gamma(x+1)]^{1/x}}{(x+1)^\alpha}$ and $\frac{[\Gamma(x+\alpha+1)]^{1/(x+\alpha})}{[\Gamma(x+1)^{1/x}}$ for $\alpha{\in}\mathbb{R}$ on ($-1,\infty$) or ($0,\infty$) are obtained, some known results are recovered, extended and generalized. Moreover, some basic properties of the logarithmically completely monotonic functions are established.