• 제목/요약/키워드: Integral representations

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EVALUATIONS OF SOME QUADRATIC EULER SUMS

  • Si, Xin;Xu, Ce
    • 대한수학회보
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    • 제57권2호
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    • pp.489-508
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    • 2020
  • This paper develops an approach to the evaluation of quadratic Euler sums that involve harmonic numbers. The approach is based on simple integral computations of polylogarithms. By using the approach, we establish some relations between quadratic Euler sums and linear sums. Furthermore, we obtain some closed form representations of quadratic sums in terms of zeta values and linear sums. The given representations are new.

EXTREMAL DISTANCE AND GREEN'S FUNCTION

  • Chung, Bo Hyun
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제1권1호
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    • pp.29-33
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    • 1994
  • There are various aspects of the solution of boundary-value problems for second-order linear elliptic equations in two independent variables. One useful method of solving such boundary-value problems for Laplace's equation is by means of suitable integral representations of solutions and these representations are obtained most directly in terms of particular singular solutions, termed Green's functions.(omitted)

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DUALITY OF WEIGHTED SUM FORMULAS OF ALTERNATING MULTIPLE T-VALUES

  • Xu, Ce
    • 대한수학회보
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    • 제58권5호
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    • pp.1261-1278
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    • 2021
  • Recently, a new kind of multiple zeta value of level two T(k) (which is called multiple T-value) was introduced and studied by Kaneko and Tsumura. In this paper, we define a kind of alternating version of multiple T-values, and study several duality formulas of weighted sum formulas about alternating multiple T-values by using the methods of iterated integral representations and series representations. Some special values of alternating multiple T-values can also be obtained.

임피던스 반 평면에 대한 Sommerfeld 적분의 Closed-Form 계산 (Exact Evaluation of a Sommerfeld Integral for the Impedance Half-Plane Problem)

  • 고일석
    • 한국전자파학회논문지
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    • 제17권8호
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    • pp.788-794
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    • 2006
  • 본 논문에서는 임피던스 반 평면 문제에서 나오는 Sommerfeld 적분의 closed-form을 계산한다. 우선 주어진 Sommerfeld 적분을 두 개의 급수 형태로 표현한다. 급수 중 하나는 exponential integral로 알려진 초월 함수로, 다른 것은 Lommel 함수로 표현이 된다. Lommel 함수 표현으로부터 주어진 Sommerfeld 적분의 closed-form을 incomplete Weber integral로 표현한다. incomplete Weber integral은 여러 분야에서 사용되고 있고 많은 성질들이 알려져 있다. 또 exponential integral 함수 표현으로부터 Sommerfeld 적분을 incomplete Gamma 함수로 근사화한다. 구한 모든 식들은 수칙 적분 결과와 비교하여 validation을 한다.

Integral Controller Design for Time-Delay Plants Using a Simplified Predictor

  • Ishihara, Tadashi;Wu, Jingwei
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2002년도 ICCAS
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    • pp.90.2-90
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    • 2002
  • A new integral controller is proposed for time-delay plants. The proposed controller has Davison type structure and utilizes a simplified state predictor instead of the optimal state predictor for the extended system. The simplified predictor is introduced by a trick similar to that used in the Smith predictor. As a systematic method for designing the proposed controller, the application of the loop transfer recovery (LTR) technique is considered. For the plant input side and the output side, explicit representations of the sensitivity matrices achieved by enforcing the formal LTR procedure using Riccati equations are obtained. A numerical example is presented to compare the asymptotic...

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MATHIEU-TYPE SERIES BUILT BY (p, q)-EXTENDED GAUSSIAN HYPERGEOMETRIC FUNCTION

  • Choi, Junesang;Parmar, Rakesh Kumar;Pogany, Tibor K.
    • 대한수학회보
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    • 제54권3호
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    • pp.789-797
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    • 2017
  • The main purpose of this paper is to present closed integral form expressions for the Mathieu-type a-series and its associated alternating version whose terms contain a (p, q)-extended Gauss' hypergeometric function. Certain upper bounds for the two series are also given.

SOME INTEGRAL REPRESENTATIONS OF THE CLAUSEN FUNCTION Cl2(x) AND THE CATALAN CONSTANT G

  • Choi, Junesang
    • East Asian mathematical journal
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    • 제32권1호
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    • pp.43-46
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    • 2016
  • The Clausen function $Cl_2$(x) arises in several applications. A large number of indefinite integrals of logarithmic or trigonometric functions can be expressed in closed form in terms of $Cl_2$(x). Very recently, Choi and Srivatava [3] and Choi [1] investigated certain integral formulas associated with $Cl_2$(x). In this sequel, we present an interesting new definite integral formula for the Clausen function $Cl_2$(x) by using a known relationship between the Clausen function $Cl_2$(x) and the generalized Zeta function ${\zeta}$(s, a). Also an interesting integral representation for the Catalan constant G is considered as one of two special cases of our main result.

On a Class of Univalent Functions Defined by Ruscheweyh Derivatives

  • SHAMS, S.;KULKARNI, S.R.;JAHANGIRI, JAY M.
    • Kyungpook Mathematical Journal
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    • 제43권4호
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    • pp.579-585
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    • 2003
  • A new class of univalent functions is defined by making use of the Ruscheweyh derivatives. We provide necessary and sufficient coefficient conditions, extreme points, integral representations, distortion bounds, and radius of starlikeness and convexity for this class.

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