• 제목/요약/키워드: Generalized gamma functions

검색결과 76건 처리시간 0.025초

CERTAIN CLASSES OF INFINITE SERIES DEDUCIBLE FROM MELLIN-BARNES TYPE OF CONTOUR INTEGRALS

  • Choi, Junesang;Agarwal, Praveen
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제20권4호
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    • pp.233-242
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    • 2013
  • Certain interesting single (or double) infinite series associated with hypergeometric functions have been expressed in terms of Psi (or Digamma) function ${\psi}(z)$, for example, see Nishimoto and Srivastava [8], Srivastava and Nishimoto [13], Saxena [10], and Chen and Srivastava [5], and so on. In this sequel, with a view to unifying and extending those earlier results, we first establish two relations which some double infinite series involving hypergeometric functions are expressed in a single infinite series involving ${\psi}(z)$. With the help of those series relations we derived, we next present two functional relations which some double infinite series involving $\bar{H}$-functions, which are defined by a generalized Mellin-Barnes type of contour integral, are expressed in a single infinite series involving ${\psi}(z)$. The results obtained here are of general character and only two of their special cases, among numerous ones, are pointed out to reduce to some known results.

A CLASS OF DEFINITE INTEGRALS

  • Kim, Insuk
    • 호남수학학술지
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    • 제39권3호
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    • pp.453-463
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    • 2017
  • The aim of this paper is to provide a class of six definite general integrals in terms of gamma function. The results are established with the help of generalized summation formulas obtained earlier by Rakha and Rathie. The results established in this paper are simple, interesting, easily established and may be useful potentially.

TWO GENERAL HYPERGEOMETRIC TRANSFORMATION FORMULAS

  • Choi, Junesang;Rathie, Arjun K.
    • 대한수학회논문집
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    • 제29권4호
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    • pp.519-526
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    • 2014
  • A large number of summation and transformation formulas involving (generalized) hypergeometric functions have been developed by many authors. Here we aim at establishing two (presumably) new general hypergeometric transformations. The results are derived by manipulating the involved series in an elementary way with the aid of certain hypergeometric summation theorems obtained earlier by Rakha and Rathie. Relevant connections of certain special cases of our main results with several known identities are also pointed out.

THE STUDY OF FLOOD FREQUENCY ESTIMATES USING CAUCHY VARIABLE KERNEL

  • Moon, Young-Il;Cha, Young-Il;Ashish Sharma
    • Water Engineering Research
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    • 제2권1호
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    • pp.1-10
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    • 2001
  • The frequency analyses for the precipitation data in Korea were performed. We used daily maximum series, monthly maximum series, and annual series. For nonparametric frequency analyses, variable kernel estimators were used. Nonparametric methods do not require assumptions about the underlying populations from which the data are obtained. Therefore, they are better suited for multimodal distributions with the advantage of not requiring a distributional assumption. In order to compare their performance with parametric distributions, we considered several probability density functions. They are Gamma, Gumbel, Log-normal, Log-Pearson type III, Exponential, Generalized logistic, Generalized Pareto, and Wakeby distributions. The variable kernel estimates are comparable and are in the middle of the range of the parametric estimates. The variable kernel estimates show a very small probability in extrapolation beyond the largest observed data in the sample. However, the log-variable kernel estimates remedied these defects with the log-transformed data.

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ON THE OSCILLATION OF SECOND-ORDER NONLINEAR DELAY DYNAMIC EQUATIONS ON TIME SCALES

  • Zhang, Quanxin;Sogn, Xia;Gao, Li
    • Journal of applied mathematics & informatics
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    • 제30권1_2호
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    • pp.219-234
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    • 2012
  • By using the generalized Riccati transformation and the inequality technique, we establish some new oscillation criterion for the second-order nonlinear delay dynamic equations $$(a(t)(x^{\Delta}(t))^{\gamma})^{\Delta}+q(t)f(x({\tau}(t)))=0$$ on a time scale $\mathbb{T}$, here ${\gamma}{\geq}1$ is the ratio of two positive odd integers with $a$ and $q$ real-valued positive right-dense continuous functions defined on $\mathbb{T}$. Our results not only extend and improve some known results, but also unify the oscillation of the second-order nonlinear delay differential equation and the second-order nonlinear delay difference equation.

First-Principles Study of the Three Polymorphs of Crystalline 1,1-Diamino-2,2-dinitrotheylene

  • Wu, Qiong;Zhu, Weihua;Xiao, Heming
    • Bulletin of the Korean Chemical Society
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    • 제34권8호
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    • pp.2281-2285
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    • 2013
  • The electronic structure, optical spectra, and thermodynamic properties of the three FOX-7 polymorphs (${\alpha}$, ${\beta}$, and ${\gamma}$) have been studied systematically using density functional theory. The LDA (CA-PZ) and generalized gradient approximation (GGA) (PW91) functions were used to relax the three FOX-7 phases without any constraint. Their density of states and partial density of states were calculated and analyzed. The band gaps for the three phases were calculated and the sequence of their sensitivity was presented. Their absorption coefficients were computed and compared. The thermodynamic functions including enthalpy (H), entropy (S), free energy (G), and heat capacity ($C_p$) for the three phases were evaluated.

CERTAIN IDENTITIES ASSOCIATED WITH GENERALIZED HYPERGEOMETRIC SERIES AND BINOMIAL COEFFICIENTS

  • Lee, Keum-Sik;Cho, Young-Joon;Choi, June-Sang
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제8권2호
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    • pp.127-135
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    • 2001
  • The main object of this paper is to present a transformation formula for a finite series involving $_3F_2$ and some identities associated with the binomial coefficients by making use of the theory of Legendre polynomials $P_{n}$(x) and some summation theorems for hypergeometric functions $_pF_q$. Some integral formulas are also considered.

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CERTAIN SUMMATION FORMULAS FOR HUMBERT'S DOUBLE HYPERGEOMETRIC SERIES Ψ2 AND Φ2

  • CHOI, JUNESANG;RATHIE, ARJUN KUMAR
    • 대한수학회논문집
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    • 제30권4호
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    • pp.439-446
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    • 2015
  • The main objective of this paper is to establish certain explicit expressions for the Humbert functions ${\Phi}_2$(a, a + i ; c ; x, -x) and ${\Psi}_2$(a ; c, c + i ; x, -x) for i = 0, ${\pm}1$, ${\pm}2$, ..., ${\pm}5$. Several new and known summation formulas for ${\Phi}_2$ and ${\Psi}_2$ are considered as special cases of our main identities.

NEW RESULTS FOR THE SERIES 2F2(x) WITH AN APPLICATION

  • Choi, Junesang;Rathie, Arjun Kumar
    • 대한수학회논문집
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    • 제29권1호
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    • pp.65-74
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    • 2014
  • The well known quadratic transformation formula due to Gauss: $$(1-x)^{-2a}{_2F_1}\[{{a,b;}\\\hfill{21}{2b;}}\;-\frac{4x}{(1-x)^2}\]={_2F_1}\[{{a,a-b+\frac{1}{2};}\\\hfill{65}{b+\frac{1}{2};}}\;x^2\]$$ plays an important role in the theory of (generalized) hypergeometric series. In 2001, Rathie and Kim have obtained two results closely related to the above quadratic transformation for $_2F_1$. Our main objective of this paper is to deduce some interesting known or new results for the series $_2F_1(x)$ by using the above Gauss's quadratic transformation and its contiguous relations and then apply our results to provide a list of a large number of integrals involving confluent hypergeometric functions, some of which are (presumably) new. The results established here are (potentially) useful in mathematics, physics, statistics, engineering, and so on.

CERTAIN NEW GENERATING RELATIONS FOR PRODUCTS OF TWO LAGUERRE POLYNOMIALS

  • CHOI, JUNESANG;RATHIE, ARJUN KUMAR
    • 대한수학회논문집
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    • 제30권3호
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    • pp.191-200
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    • 2015
  • Generating functions play an important role in the investigation of various useful properties of the sequences which they generate. Exton [13] presented a very general double generating relation involving products of two Laguerre polynomials. Motivated essentially by Exton's derivation [13], the authors aim to show how one can obtain nineteen new generating relations associated with products of two Laguerre polynomials in the form of a single result. We also consider some interesting and potentially useful special cases of our main findings.