The exact relationship between the bending solutions of functionally graded material (FGM) beams based on the Levinson beam theory and those of the correspond- ing homogenous beams based on the classical beam theory...The exact relationship between the bending solutions of functionally graded material (FGM) beams based on the Levinson beam theory and those of the correspond- ing homogenous beams based on the classical beam theory is presented for the material properties of the FGM beams changing continuously in the thickness direction. The de- flection, the rotational angle, the bending moment, and the shear force of FGM Levinson beams (FGMLBs) are given analytically in terms of the deflection of the reference ho- mogenous Euler-Bernoulli beams (HEBBs) with the same loading, geometry, and end supports. Consequently, the solution of the bending of non-homogenous Levinson beams can be simplified to the calculation of transition coefficients, which can be easily deter- mined by variation of the gradient of material properties and the geometry of beams. This is because the classical beam theory solutions of homogenous beams can be eas- ily determined or are available in the textbook of material strength under a variety of boundary conditions. As examples, for different end constraints, particular solutions are given for the FGMLBs under specified loadings to illustrate validity of this approach. These analytical solutions can be used as benchmarks to check numerical results in the investigation of static bending of FGM beams based on higher-order shear deformation theories.展开更多
For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n, which is relatively prime to n. o:(n) is defined to be the number of different pri...For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n, which is relatively prime to n. o:(n) is defined to be the number of different prime divisors of n. In order to know the solvability of the function of φ(φ(φ(n))) = 2^ω(n), properties of the number theoretical function φ(φ(n)) is studied in the paper.展开更多
For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n which are relatively prime to n. w(n) is defined to be the number of different prime...For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n which are relatively prime to n. w(n) is defined to be the number of different prime divisors of n. Some kind of equations involving Euler's function is studied in the paper.展开更多
We study the nonlinear parabolic equations for travelling wave solutions of Burger’s equations. The purpose of the present work is to study various types of Burger’s equations describing waves and those are based on...We study the nonlinear parabolic equations for travelling wave solutions of Burger’s equations. The purpose of the present work is to study various types of Burger’s equations describing waves and those are based on nonlinear equations. We focus on to describe the analytic solution in the special pattern of travelling wave solutions using tan-cot function method. We discuss about inviscid and viscous version of Burger’s equation for fluid flow and investigate the effects of internal friction of a fluid via Reynolds number. By changing the velocity amplitude, the nature of flows with shock wave and disturbance are observed. For numerical solutions, the Crank-Nicolson scheme is introduced to establish the wave solutions.展开更多
Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this...Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this paper with the form of-([10α(φ′)^(2)]φ′)′=λf(φ(x)),whereλ>0 is a real parameter,f∈C 2(0,+∞)is a nonlinear function.We are interested in the exact number of positive solutions of the above nonlinear equation.We specifically develop for the problem combined with a careful analysis of a time-map method.展开更多
基金supported by the National Natural Science Foundation of China(No.11272278)
文摘The exact relationship between the bending solutions of functionally graded material (FGM) beams based on the Levinson beam theory and those of the correspond- ing homogenous beams based on the classical beam theory is presented for the material properties of the FGM beams changing continuously in the thickness direction. The de- flection, the rotational angle, the bending moment, and the shear force of FGM Levinson beams (FGMLBs) are given analytically in terms of the deflection of the reference ho- mogenous Euler-Bernoulli beams (HEBBs) with the same loading, geometry, and end supports. Consequently, the solution of the bending of non-homogenous Levinson beams can be simplified to the calculation of transition coefficients, which can be easily deter- mined by variation of the gradient of material properties and the geometry of beams. This is because the classical beam theory solutions of homogenous beams can be eas- ily determined or are available in the textbook of material strength under a variety of boundary conditions. As examples, for different end constraints, particular solutions are given for the FGMLBs under specified loadings to illustrate validity of this approach. These analytical solutions can be used as benchmarks to check numerical results in the investigation of static bending of FGM beams based on higher-order shear deformation theories.
基金the National Natural Science Foundation of China(10671056)
文摘For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n, which is relatively prime to n. o:(n) is defined to be the number of different prime divisors of n. In order to know the solvability of the function of φ(φ(φ(n))) = 2^ω(n), properties of the number theoretical function φ(φ(n)) is studied in the paper.
基金Foundation item: Supported by the National Natural Science Foundation of China(10671056)
文摘For any given positive integer n ≥ 1, the Euler function φ(n) is defined to be the number of positive integers not exceeding n which are relatively prime to n. w(n) is defined to be the number of different prime divisors of n. Some kind of equations involving Euler's function is studied in the paper.
文摘We study the nonlinear parabolic equations for travelling wave solutions of Burger’s equations. The purpose of the present work is to study various types of Burger’s equations describing waves and those are based on nonlinear equations. We focus on to describe the analytic solution in the special pattern of travelling wave solutions using tan-cot function method. We discuss about inviscid and viscous version of Burger’s equation for fluid flow and investigate the effects of internal friction of a fluid via Reynolds number. By changing the velocity amplitude, the nature of flows with shock wave and disturbance are observed. For numerical solutions, the Crank-Nicolson scheme is introduced to establish the wave solutions.
基金Supported by National Natural Science Foundation of He’nan Province of China(Grant No.222300420416)National Natural Science Foundation of China(Grant Nos.11471099,11971148)Graduate Talents Program of Henan University(Grant No.SYLYC2022078).
文摘Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation,we investigate the polynomial function model in Born-Infeld theory in this paper with the form of-([10α(φ′)^(2)]φ′)′=λf(φ(x)),whereλ>0 is a real parameter,f∈C 2(0,+∞)is a nonlinear function.We are interested in the exact number of positive solutions of the above nonlinear equation.We specifically develop for the problem combined with a careful analysis of a time-map method.