• 제목/요약/키워드: Legendre function

검색결과 76건 처리시간 0.021초

Mindlin 판의 강성 과잉 현상과 고유치에 관한 연구 (Study on The Stiffness Locking Phenomenon and Eigen Problem in Mindlin Plate)

  • 김용우;박춘수;민옥기
    • 대한기계학회논문집
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    • 제15권2호
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    • pp.445-454
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    • 1991
  • In this thesis, Mindlin plate element with nine nodes and three degrees-of-freedom at each node is formulated and is employed in eigen-analysis of a rectangular plates in order to alleviate locking phenomenon of eigenvalues. Eigenvalues and their modes may be locked if conventional $C_{0}$-isoparametric element is used. In order to reduce stiffness locking phenomenon, two methods (1, the general reduced and selective integration, 2, the new element that use of modified shape function) are studied. Additionally in order to reduce the error due to mass matrix, two mass matrixes (1, Gauss-Legendre mass matrix, 2, Gauss-Lobatto mass matrix) are considered. The results of eigen-analysis for two models (the square plate with all edges simply-supported and all edges built-in), computed by two methods for stiffness matrix and by two mass matrixes are compared with theoretical solutions and conventional numerical solutions. These comparisons show that the performance of the two methods with Gauss-Lobatto mass matrix is better than that of the conventional plate element. But, by considering the spurious rigid body motions, the element which employs modified shape function with full integration and Gauss-Lobatto mass matrix can elevate the accuracy and convergence of numerical solutions.

최적의 상호상관관계를 갖는 이진 수열의 설계 (Design of Binary Sequences with Optimal Cross-correlation Values)

  • 최언숙;조성진
    • 한국전자통신학회논문지
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    • 제6권4호
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    • pp.539-544
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    • 2011
  • 적당한 정수 $n({\geq}1)$에 대하여 2-valued 자기상관관계를 갖는 주기가 $2^n-1$인 균형 이진 수열(balanced binary sequences)은 대역확산 통신 시스템(spread-spectrum communication system)에서 많이 응용되고 있다. 본 논문에서는 르장드르 수열에 의해 구성되는 새로운 3-valued 비선형 이진 수열을 제안한다. 이 수열은 유한체 위에서 트레이스를 이용해 생성하는 가장 우수한 수열인 m-수열, GMW 수열, Kasami 수열, No 수열을 모두 포함한다. 제안된 수열은 Klapper에 의해 제안된 이차형식 수열보다 더 낮은 상호상관관계를 갖는다.

Relation between the Irreducible Polynomials that Generates the Same Binary Sequence Over Odd Characteristic Field

  • Ali, Md. Arshad;Kodera, Yuta;Park, Taehwan;Kusaka, Takuya;Nogmi, Yasuyuki;Kim, Howon
    • Journal of information and communication convergence engineering
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    • 제16권3호
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    • pp.166-172
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    • 2018
  • A pseudo-random sequence generated by using a primitive polynomial, trace function, and Legendre symbol has been researched in our previous work. Our previous sequence has some interesting features such as period, autocorrelation, and linear complexity. A pseudo-random sequence widely used in cryptography. However, from the aspect of the practical use in cryptographic systems sequence needs to generate swiftly. Our previous sequence generated by utilizing a primitive polynomial, however, finding a primitive polynomial requires high calculating cost when the degree or the characteristic is large. It’s a shortcoming of our previous work. The main contribution of this work is to find some relation between the generated sequence and irreducible polynomials. The purpose of this relationship is to generate the same sequence without utilizing a primitive polynomial. From the experimental observation, it is found that there are (p - 1)/2 kinds of polynomial, which generates the same sequence. In addition, some of these polynomials are non-primitive polynomial. In this paper, these relationships between the sequence and the polynomials are shown by some examples. Furthermore, these relationships are proven theoretically also.

ON MATRIX POLYNOMIALS ASSOCIATED WITH HUMBERT POLYNOMIALS

  • Pathan, M.A.;Bin-Saad, Maged G.;Al-Sarahi, Fadhl
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제21권3호
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    • pp.207-218
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    • 2014
  • The principal object of this paper is to study a class of matrix polynomials associated with Humbert polynomials. These polynomials generalize the well known class of Gegenbauer, Legendre, Pincherl, Horadam, Horadam-Pethe and Kinney polynomials. We shall give some basic relations involving the Humbert matrix polynomials and then take up several generating functions, hypergeometric representations and expansions in series of matrix polynomials.

CERTAIN INTEGRAL FORMULAS ASSOCIATED WITH ALEPH (ℵ)-FUNCTION

  • Agarwal, Praveen;Jain, Shilpi;Karimov, Erkinjon T.;Prajapati, Jyotindra C.
    • 대한수학회논문집
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    • 제32권2호
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    • pp.305-319
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    • 2017
  • Recently many authors have investigated so-called Aleph (${\aleph}$)-function and its various properties. Here, in this paper, we aim at establishing certain integral formulas involving the Aleph (${\aleph}$)-function. Precisely, integrals with product of Aleph (${\aleph}$)-function with Jacobi polynomials, Bessel Maitland function, general class of polynomials were under consideration. Some interesting special cases of our main result are also considered and shown to be connected with certain known ones.

FRACTIONAL CALCULUS FORMULAS INVOLVING $\bar{H}$-FUNCTION AND SRIVASTAVA POLYNOMIALS

  • Kumar, Dinesh
    • 대한수학회논문집
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    • 제31권4호
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    • pp.827-844
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    • 2016
  • Here, in this paper, we aim at establishing some new unified integral and differential formulas associated with the $\bar{H}$-function. Each of these formula involves a product of the $\bar{H}$-function and Srivastava polynomials with essentially arbitrary coefficients and the results are obtained in terms of two variables $\bar{H}$-function. By assigning suitably special values to these coefficients, the main results can be reduced to the corresponding integral formulas involving the classical orthogonal polynomials including, for example, Hermite, Jacobi, Legendre and Laguerre polynomials. Furthermore, the $\bar{H}$-function occurring in each of main results can be reduced, under various special cases.

CERTAIN IMAGE FORMULAS OF (p, 𝜈)-EXTENDED GAUSS' HYPERGEOMETRIC FUNCTION AND RELATED JACOBI TRANSFORMS

  • Chopra, Purnima;Gupta, Mamta;Modi, Kanak
    • 대한수학회논문집
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    • 제37권4호
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    • pp.1055-1072
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    • 2022
  • Our aim is to establish certain image formulas of the (p, 𝜈)-extended Gauss' hypergeometric function Fp,𝜈(a, b; c; z) by using Saigo's hypergeometric fractional calculus (integral and differential) operators. Corresponding assertions for the classical Riemann-Liouville(R-L) and Erdélyi-Kober(E-K) fractional integral and differential operators are deduced. All the results are represented in terms of the Hadamard product of the (p, 𝜈)-extended Gauss's hypergeometric function Fp,𝜈(a, b; c; z) and Fox-Wright function rΨs(z). We also established Jacobi and its particular assertions for the Gegenbauer and Legendre transforms of the (p, 𝜈)-extended Gauss' hypergeometric function Fp,𝜈(a, b; c; z).

Numerical Quadrature for the Prandtl Meyer Function at High Temperature with Application for Air

  • Zebbiche, Toufik
    • International Journal of Aeronautical and Space Sciences
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    • 제9권2호
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    • pp.9-17
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    • 2008
  • When the stagnation temperature of the combustion chamber or ambient air increases, the specific heats and their ratio do not remain constant any more, and start to vary with this temperature. The gas remains perfect, except, it will be calorically imperfect and thermally perfect. A new generalized form of the Prandtl Meyer function is developed, by adding the effect of variation of this temperature, lower than the threshold of dissociation. The new relation is presented in the form of integral of a complex analytical function, having an infinite derivative at the critical temperature. A robust numerical integration quadrature is presented in this context. The classical form of the Prandtl Meyer function of a perfect gas becomes a particular case of the developed form. The comparison is made with the perfect gas model for aim to present a limit of its application. The application is for air.

Random Regression Models Are Suitable to Substitute the Traditional 305-Day Lactation Model in Genetic Evaluations of Holstein Cattle in Brazil

  • Padilha, Alessandro Haiduck;Cobuci, Jaime Araujo;Costa, Claudio Napolis;Neto, Jose Braccini
    • Asian-Australasian Journal of Animal Sciences
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    • 제29권6호
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    • pp.759-767
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    • 2016
  • The aim of this study was to compare two random regression models (RRM) fitted by fourth ($RRM_4$) and fifth-order Legendre polynomials ($RRM_5$) with a lactation model (LM) for evaluating Holstein cattle in Brazil. Two datasets with the same animals were prepared for this study. To apply test-day RRM and LMs, 262,426 test day records and 30,228 lactation records covering 305 days were prepared, respectively. The lowest values of Akaike's information criterion, Bayesian information criterion, and estimates of the maximum of the likelihood function (-2LogL) were for $RRM_4$. Heritability for 305-day milk yield (305MY) was 0.23 ($RRM_4$), 0.24 ($RRM_5$), and 0.21 (LM). Heritability, additive genetic and permanent environmental variances of test days on days in milk was from 0.16 to 0.27, from 3.76 to 6.88 and from 11.12 to 20.21, respectively. Additive genetic correlations between test days ranged from 0.20 to 0.99. Permanent environmental correlations between test days were between 0.07 and 0.99. Standard deviations of average estimated breeding values (EBVs) for 305MY from $RRM_4$ and $RRM_5$ were from 11% to 30% higher for bulls and around 28% higher for cows than that in LM. Rank correlations between RRM EBVs and LM EBVs were between 0.86 to 0.96 for bulls and 0.80 to 0.87 for cows. Average percentage of gain in reliability of EBVs for 305-day yield increased from 4% to 17% for bulls and from 23% to 24% for cows when reliability of EBVs from RRM models was compared to those from LM model. Random regression model fitted by fourth order Legendre polynomials is recommended for genetic evaluations of Brazilian Holstein cattle because of the higher reliability in the estimation of breeding values.

초 고차항 구 조화 중력모델링에 의한 상향 연속의 정확도 검증 (Accuracy Assessment of the Upward Continuation using the Gravity Model from Ultra-high Degree Spherical Harmonics)

  • 권재현;이종기
    • 한국측량학회지
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    • 제24권2호
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    • pp.183-191
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    • 2006
  • 최대 차수 10800의 초 고차 구 조화함수를 전개하여 중력을 모델링 하고, 이를 이용하여 상향 연속의 정확도를 검증하였다. 초 고차 구조화 함수에 의한 중력 모델링에 있어 수치계산적 난점인 르장드르 함수의 언더플로와 오버플로를 128 비트 연산에 의하여 성공적으로 수행하였으며, 이를 이용하여 지오이드상의 중력이상값을 공간 상도 $1'{\times}1'$ 으로 계산하였다. 생성된 중력이상값에 다양한 크기의 잡음을 첨가하고 자료의 간격을 달리하여 상향연속을 수행하였으며, 이로부터 도출된 중력 섭동 벡터와 중력 모델로부터 직접 계산된 섭동 벡터와의 비교를 통하여 실제적인 상향연속의 정확도를 할당하였다. 상향연속 방법의 비교에 있어, 직접방법이 포아송 방법에 비해 월등히 좋은 정확도를 보였고, 지상 중력자료의 잡음이 적을수록 또한 자료의 간격이 작을수록 상향연속에 의한 중력 섭동벡터의 정확도가 높게 나타남을 확인하였다. 특히 차세대 관성항법장치의 정밀 항법을 위한 중력의 필요조건인 5mGal의 정확도를 위해선, 지상 중력의 잡음 정도가 5mGal 이하, 자료의 간격이 2arcmin 이하이어야 함을 도출하였다.