• 제목/요약/키워드: Zagreb

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Improvement of Jensen's Inequality in terms of Gâteaux Derivatives for Convex Functions in Linear Spaces with Applications

  • Khan, Muhammad Adil;Khalid, Sadia;Pecaric, Josip
    • Kyungpook Mathematical Journal
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    • 제52권4호
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    • pp.495-511
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    • 2012
  • In this paper, we prove some inequalities in terms of G$\hat{a}$teaux derivatives for convex functions defined on linear spaces and also give improvement of Jensen's inequality. Furthermore, we give applications for norms, mean $f$-deviations and $f$-divergence measures.

SUM FORMULAE OF GENERALIZED FIBONACCI AND LUCAS NUMBERS

  • Cerin, Zvonko;Bitim, Bahar Demirturk;Keskin, Refik
    • 호남수학학술지
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    • 제40권1호
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    • pp.199-210
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    • 2018
  • In this paper we obtain some formulae for several sums of generalized Fibonacci numbers $U_n$ and generalized Lucas numbers $V_n$ and their dual forms $G_n$ and $H_n$ by using extensions of an interesting identity by A. R. Amini for Fibonacci numbers to these four kinds of generalizations and their first and second derivatives.

ON SOME NEW NONLINEAR RETARDED INTEGRAL INEQUALITIES WITH ITERATED INTEGRALS AND THEIR APPLICATIONS

  • Ma, Qing-Hua;Pecaric, Josip
    • 대한수학회지
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    • 제45권2호
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    • pp.331-353
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    • 2008
  • Some new nonlinear retarded integral inequalities of Gronwall-like type are established, which mainly generalized some results given by Cho, Dragomir and Kim (J. Korean Math. Soc. 43 (2006), No.3, pp. 563-578) and can be used in the analysis of various problems in the theory of certain classes of differential equations and integral equations. Applications examples are also indicated.

ON CERTAIN NEW NONLINEAR RETARDED INTEGRAL INEQUALITIES FOR FUNCTIONS IN TWO VARIABLES AND THEIR APPLICATIONS

  • Ma, Qing-Hua;Pecaric, Josip
    • 대한수학회지
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    • 제45권1호
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    • pp.121-136
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    • 2008
  • Some new explicit bounds on the solutions to a class of new nonlinear retarded Volterra-Fredholm type integral inequalities in two independent variables are established, which can be used as effective tools in the study of certain integral equations. Some examples of application are also indicated.

MAGNETIC CURVES IN ℍ3 × ℝ

  • Erjavec, Zlatko;Inoguchi, Jun-ichi
    • 대한수학회지
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    • 제58권6호
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    • pp.1501-1511
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    • 2021
  • In this paper we study magnetic trajectories on ℍ3 × ℝ with respect to the strictly almost Kähler structure. We find three types of magnetic curves which correspond to the almost complex structure compatible to the product metric on ℍ3 × ℝ.

STUDY ON LINE GRAPH OF SOME GRAPH OPERATORS OF CHEMICAL STRUCTURES VIA F AND M1 INDICES

  • P.S. HEMAVATHI;M. MANJUNATH;M. PRALAHAD;S.M. VEERESH
    • Journal of applied mathematics & informatics
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    • 제42권1호
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    • pp.159-167
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    • 2024
  • The Topological indices are known as Mathematical characterization of molecules. In this paper, we have studied line graph of subdivision and semi-total point graph of triangular benzenoid, polynomino chains of 8-cycles and graphene sheet through forgotten and first Zagreb indices.

Thrust force and base bending moment acting on a horizontal axis wind turbine with a high tip speed ratio at high yaw angles

  • Bosnar, Danijel;Kozmar, Hrvoje;Pospisil, Stanislav;Machacek, Michael
    • Wind and Structures
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    • 제32권5호
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    • pp.471-485
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    • 2021
  • Onshore wind turbines may experience substantially different wind loads depending on their working conditions, i.e. rotation velocity of rotor blades, incoming freestream wind velocity, pitch angle of rotor blades, and yaw angle of the wind-turbine tower. In the present study, aerodynamic loads acting on a horizontal axis wind turbine were accordingly quantified for the high tip speed ratio (TSR) at high yaw angles because these conditions have previously not been adequately addressed. This was analyzed experimentally on a small-scale wind-turbine model in a boundary layer wind tunnel. The wind-tunnel simulation of the neutrally stratified atmospheric boundary layer (ABL) developing above a flat terrain was generated using the Counihan approach. The ABL was simulated to achieve the conditions of a wind-turbine model operating in similar inflow conditions to those of a prototype wind turbine situated in the lower atmosphere, which is another important aspect of the present work. The ABL and wind-turbine simulation length scale factors were the same (S=300) in order to satisfy the Jensen similarity criterion. Aerodynamic loads experienced by the wind-turbine model subjected to the ABL simulation were studied based on the high frequency force balance (HFFB) measurements. Emphasis was put on the thrust force and the bending moment because these two load components have previously proven to be dominant compared to other load components. The results indicate several important findings. The loads were substantially higher for TSR=10 compared to TSR=5.6. In these conditions, a considerable load reduction was achieved by pitching the rotor blades. For the blade pitch angle at 90°, the loads were ten times lower than the loads of the rotating wind-turbine model. For the blade pitch angle at 12°, the loads were at 50% of the rotating wind-turbine model. The loads were reduced by up to 40% through the yawing of the wind-turbine model, which was observed both for the rotating and the parked wind-turbine model.

EXTREMAL F-INDICES FOR BICYCLIC GRAPHS WITH k PENDANT VERTICES

  • Amin, Ruhul;Nayeem, Sk. Md. Abu
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제27권4호
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    • pp.171-186
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    • 2020
  • Long back in 1972, it was shown that the sum of the squares of vertex degrees and the sum of cubes of vertex degrees of a molecular graph both have large correlations with total 𝜋-electron energy of the molecule. Later on, the sum of squares of vertex degrees was named as first Zagreb index and became one of the most studied molecular graph parameter in the field of chemical graph theory. Whereas, the other sum remained almost unnoticed until recently except for a few occasions. Thus it got the name "forgotten" index or F-index. This paper investigates extremal graphs with respect to F-index among the class of bicyclic graphs with n vertices and k pendant vertices, 0 ≤ k ≤ n - 4. As consequences, we obtain the bicyclic graphs with largest and smallest F-indices.

Probiotics in Children: What Is the Evidence?

  • Hojsak, Iva
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제20권3호
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    • pp.139-146
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    • 2017
  • The number of papers discussing probiotics increases tremendously that limits the possibility for primary care physicians and clinicians to stay updated. Therefore, the aim of this paper will be to summarize available evidence of probiotic use in well-defined clinical indications of importance for pediatricians. Based on currently available evidence certain probiotic strains (Lactobacillus rhamnosus GG [LGG] and Saccharomyces boulardii) have proven effect in the treatment of acute gastroenteritis and prevention of antibiotic associated diarrhea. Furthermore, LGG was proven to be effective in prevention of nosocomial diarrhea and respiratory tract infection in day care centers. In conclusion, not all probiotic strains have same efficacy for all clinical indications, therefore, only strains with proven efficacy and safety should be recommended.

SOME INEQUALITIES FOR THE HARMONIC TOPOLOGICAL INDEX

  • MILOVANOVIC, E.I.;MATEJIC, M.M.;MILOVANOVIC, I.Z.
    • Journal of applied mathematics & informatics
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    • 제36권3_4호
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    • pp.307-315
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    • 2018
  • Let G be a simple connected graph with n vertices and m edges, with a sequence of vertex degrees $d_1{\geq}d_2{\geq}{\cdots}{\geq}d_n$ > 0. A vertex-degree topological index, referred to as harmonic index, is defined as $H={\sum{_{i{\sim}j}}{\frac{2}{d_i+d_j}}$, where i ~ j denotes the adjacency of vertices i and j. Lower and upper bounds of the index H are obtained.