• 제목/요약/키워드: solutions

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EXISTENCE OF POSITIVE T-PERIODIC SOLUTIONS OF RATIO-DEPENDENT PREDATOR-PREY SYSTEMS

  • Ryu, Kimun
    • Journal of the Chungcheong Mathematical Society
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    • 제34권1호
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    • pp.27-35
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    • 2021
  • We study the existence of positive T-periodic solutions of ratio-dependent predator-prey systems with time periodic and spatially dependent coefficients. The fixed point theorem by H. Amann is used to obtain necessary and sufficient conditions for the existence of positive T-periodic solutions.

EXISTENCE OF PERIODIC SOLUTIONS IN FERROELECTRIC LIQUID CRYSTALS

  • Park, Jinhae
    • Journal of the Chungcheong Mathematical Society
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    • 제23권3호
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    • pp.571-588
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    • 2010
  • We introduce the Landau-de Gennes model in order to understand molecular structures in ferroelectric liquid crystals. We investigate equilibrium configurations of the governing energy functional by means of bifurcation analysis. In particular, we obtain periodic solutions of the functional, which is a signature of a rich variety of applications of ferroelectric materials.

FUZZY SOLUTIONS OF ABEL DIFFERENTIAL EQUATIONS USING RESIDUAL POWER SERIES METHOD

  • N. NITHYADEVI;P. PRAKASH
    • Journal of applied mathematics & informatics
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    • 제41권1호
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    • pp.71-82
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    • 2023
  • In this article, we find the approximate solutions of Abel differential equation (ADE) with uncertainty using residual power series (RPS) method. This method helps to calculate the sequence of solutions of ADE. Finally, numerical illustrations demonstrate the applicability of the method.

ON THE GROWTH OF ALGEBROID SOLUTIONS OF ALGEBRAIC DIFFERENTIAL EQUATIONS

  • Manli Liu;Linlin Wu
    • Bulletin of the Korean Mathematical Society
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    • 제61권3호
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    • pp.597-610
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    • 2024
  • Using the Nevanlinna value distribution theory of algebroid functions, this paper investigates the growth of two types of complex algebraic differential equation with algebroid solutions and obtains two results, which extend the growth of complex algebraic differential equation with meromorphic solutions obtained by Gao [4].

TRAVELING WAVES OF AN SIRS EPIDEMIC MODEL WITH SPATIAL DIFFUSION AND TIME DELAY

  • Du, Yanke;Xu, Rui
    • Journal of applied mathematics & informatics
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    • 제30권3_4호
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    • pp.635-646
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    • 2012
  • This paper is concerned with an SIRS epidemic model with spatial diffusion and time delay representing the length of the immunity period. By using a new cross iteration scheme and Schauder's fixed point theorem, we reduce the existence of traveling wave solutions to the existence of a pair of upper-lower solutions. By constructing a newfashioned pair of upper-lower solutions, we derive the existence of a traveling wave solution connecting the uninfected steady state and the infected steady state.

THREE-POINT BOUNDARY VALUE PROBLEMS FOR HIGHER ORDER NONLINEAR FRACTIONAL DIFFERENTIAL EQUATIONS

  • Khan, Rahmat Ali
    • Journal of applied mathematics & informatics
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    • 제31권1_2호
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    • pp.221-228
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    • 2013
  • The method of upper and lower solutions and the generalized quasilinearization technique is developed for the existence and approximation of solutions to boundary value problems for higher order fractional differential equations of the type $^c\mathcal{D}^qu(t)+f(t,u(t))=0$, $t{\in}(0,1),q{\in}(n-1,n],n{\geq}2$ $u^{\prime}(0)=0,u^{\prime\prime}(0)=0,{\ldots},u^{n-1}(0)=0,u(1)={\xi}u({\eta})$, where ${\xi},{\eta}{\in}(0,1)$, the nonlinear function f is assumed to be continuous and $^c\mathcal{D}^q$ is the fractional derivative in the sense of Caputo. Existence of solution is established via the upper and lower solutions method and approximation of solutions uses the generalized quasilinearization technique.

An Iterative Posterior Preference Articulation Approach to Dual Response Surface Optimization (쌍대반응표면최적화를 위한 반복적 선호도사후제시법)

  • Jeong, In-Jun
    • Journal of Korean Society for Quality Management
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    • 제40권4호
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    • pp.481-496
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    • 2012
  • Purpose: This paper aims at improving inefficiency of an existing posterior preference articulation method proposed for dual response surface optimization. The method generates a set of non-dominated solutions and then allows a decision maker (DM) to select the best solution among them through an interval selection strategy. Methods: This paper proposes an iterative posterior preference articulation method, which repeatedly generates the predetermined number of non-dominated solutions in an interval which becomes gradually narrower over rounds. Results: The existing method generates a good number of non-dominated solutions not used in the DM's selection process, while the proposed method generates the minimal number of non-dominated solutions necessitated in the selection process. Conclusion: The proposed method enables a satisfactory compromise solution to be achieved with minimal cognitive burden of the DM as well as with light computation load in generating non-dominated solutions.

An Attribute Replicating Vertical File Partition Method by Genetic Algorithm (유전알고리듬을 이용한 속성의 중복 허용 파일 수직분할 방법)

  • 김재련;유종찬
    • The Journal of Information Technology and Database
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    • 제6권2호
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    • pp.71-86
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    • 1999
  • The performance of relational database is measured by the number of disk accesses necessary to transfer data from disk to main memory. The paper proposes to vertically partition relations into fragments and to allow attribute replication to reduce the number of disk accesses. To reduce the computational time, heuristic search method using genetic algorithm is used. Genetic algorithm used employs a rank-based-sharing fitness function and elitism. Desirable parameters of genetic algorithm are obtained through experiments and used to find the solutions. Solutions of attribute replication and attribute non-replication problems are compared. Optimal solutions obtained by branch and bound method and by heuristic solutions(genetic algorithm) are also discussed. The solution method proposed is able to solve large-sized problems within acceptable time limit and shows solutions near the optimal value.

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UNIFYING STATIONARY EQUATIONS FOR GENERALIZED CANONICAL CORRELATION ANALYSIS

  • Kang Hyun-Cheol;Kim Kee-Young
    • Journal of the Korean Statistical Society
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    • 제35권2호
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    • pp.143-156
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    • 2006
  • In the present paper, various solutions for generalized canonical correlation analysis (GCCA) are considered depending on the criteria and constraints. For the comparisons of some characteristics of the solutions, we provide with certain unifying stationary equations which might to also useful to obtain various generalized canonical correlation analysis solutions. In addition, we suggest an approach for the generalized canonical correlation analysis by exploiting the concept of maximum eccentricity originally de-signed to test the internal independence structure. The solutions, including new one, are compared through unifying stationary equations and by using some numerical illustrations. A type of iterative procedure for the GCCA solutions is suggested and some numerical examples are provided to illustrate several GCCA methods.