• Title/Summary/Keyword: generalized equations

Search Result 756, Processing Time 0.02 seconds

Weak forms of generalized governing equations in theory of elasticity

  • Shi, G.;Tang, L.
    • Interaction and multiscale mechanics
    • /
    • v.1 no.3
    • /
    • pp.329-337
    • /
    • 2008
  • This paper presents the derivation of the generalized governing equations in theory of elasticity, their weak forms and the some applications in the numerical analysis of structural mechanics. Unlike the differential equations in classical elasticity theory, the generalized equations of the equilibrium and compatibility equations presented here take the form of integral equations, and the generalized equilibrium equations contain the classical differential equations and the boundary conditions in a single equation. By using appropriate test functions, the weak forms of these generalized governing equations can be established. It can be shown that various variational principles in structural analysis are merely the special cases of these weak forms of generalized governing equations in elasticity. The present weak forms of elasticity equations extend greatly the choices of the trial functions for approximate solutions in the numerical analysis of various engineering problems. Therefore, the weak forms of generalized governing equations in elasticity provide a powerful modeling tool in the computational structural mechanics.

APPROXIMATION OF SOLUTIONS FOR GENERALIZED WIENER-HOPF EQUATIONS AND GENERALIZED VARIATIONAL INEQUALITIES

  • Gu, Guanghui;Su, Yongfu
    • Journal of applied mathematics & informatics
    • /
    • v.28 no.1_2
    • /
    • pp.465-472
    • /
    • 2010
  • The purpose of this article is to introduce a new generalized class of the Wiener-Hopf equations and a new generalized class of the variational inequalities. Using the projection technique, we show that the generalized Wiener-Hopf equations are equivalent to the generalized variational inequalities. We use this alternative equivalence to suggest and analyze an iterative scheme for finding the solution of the generalized Wiener-Hopf equations and the solution of the generalized variational inequalities. The results presented in this paper may be viewed as significant and improvement of the previously known results. In special, our results improve and extend the resent results of M.A. Noor and Z.Y.Huang[M.A. Noor and Z.Y.Huang, Wiener-Hopf equation technique for variational inequalities and nonexpansive mappings, Appl. Math. Comput.(2007), doi:10.1016/j.amc.2007.02.117].

ON A CLASS OF GENERALIZED LOGARITHMIC FUNCTIONAL EQUATIONS

  • Chung, Jae-Young
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.22 no.3
    • /
    • pp.325-332
    • /
    • 2009
  • Reducing the generalized logarithmic functional equations to differential equations in the sense of Schwartz distributions, we find the locally integrable solutions of the equations.

  • PDF

A New Approach for Motion Control of Constrained Mechanical Systems: Using Udwadia-Kalaba′s Equations of Motion

  • Joongseon Joh
    • International Journal of Precision Engineering and Manufacturing
    • /
    • v.2 no.4
    • /
    • pp.61-68
    • /
    • 2001
  • A new approach for motion control of constrained mechanical systems is proposed in this paper. The approach uses a new equations of motion which is proposed by Udwadia and Kalaba and named Udwadia-Kalaba's equations of motion in this paper. This paper reveals that the Udwadia-Kalaba's equations of motion is more adequate to model constrained mechanical systems rather than the famous Lagrange's equations of motion at least for control purpose. The proposed approach coverts most of constraints including holonomic and nonholonomic constraints. Comparison of simulation results of two systems which are well-known in the literature show the superiority of the proposed approach. Furthermore, a special constrained mechanical system which includes nonlinear generalized velocities in its constraint equations, which has been considered to be difficult to control, can be controlled easily. It shows the possibility of the proposed approach to being a general framework for motion control of constrained mechanical systems with various kinds of constraints.

  • PDF

A recursive approach for mechanical system design sensitivity analysis

  • Daesung Bae
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.10 no.1
    • /
    • pp.101-111
    • /
    • 2001
  • Recursive formulas have been effective in solving the equations of motion for large scale constratined mechanical sys-tems. However, derivation of the formulas has been limited to individual terms in the equations of motion, such as veloci-ty, acceleration. and generalized forces. The recursive formulas are generalized in this paper. The velocity transformation method is employed to transform the equations of motion from Cartesian to the joint spaces. Computational structure of the equations of motion in the joint space is carefully examined to classify all necessary computational operations into sev-eral categories. The generalized recursive formula for each category is then developed and applied whenever such a cate-gory of computation is encountered. Since the velocity transformation method yields the equations of motion in a compact form and computational efficiency is achieved by generalized recursive formulas, the proposed method is not only easy to implement but is also efficient. A library of generalized recursive formulas is developed to implement a dynamic analysis algorithm using backward difference.

  • PDF

GENERALIZED JENSEN'S FUNCTIONAL EQUATIONS AND APPROXIMATE ALGEBRA HOMOMORPHISMS

  • Bae, Jae-Hyeong;Park, Won-Gil
    • Bulletin of the Korean Mathematical Society
    • /
    • v.39 no.3
    • /
    • pp.401-410
    • /
    • 2002
  • We prove the generalized Hyers-Ulam-Rassias stability of generalized Jensen's functional equations in Banach modules over a unital $C^{*}$-algebra. It is applied to show the stability of algebra homomorphisms between Banach algebras associated with generalized Jensen's functional equations in Banach algebras.

GENERALIZED INVERSES IN NUMERICAL SOLUTIONS OF CAUCHY SINGULAR INTEGRAL EQUATIONS

  • Kim, S.
    • Communications of the Korean Mathematical Society
    • /
    • v.13 no.4
    • /
    • pp.875-888
    • /
    • 1998
  • The use of the zeros of Chebyshev polynomial of the first kind $T_{4n+4(x}$ ) and second kind $U_{2n+1}$ (x) for Gauss-Chebyshev quad-rature and collocation of singular integral equations of Cauchy type yields computationally accurate solutions over other combinations of $T_{n}$ /(x) and $U_{m}$(x) as in [8]. We show that the coefficient matrix of the overdetermined system has the generalized inverse. We estimate the residual error using the norm of the generalized inverse.e.

  • PDF

LOCAL CONVERGENCE OF NEWTON-LIKE METHODS FOR GENERALIZED EQUATIONS

  • Argyros, Ioannis K.
    • East Asian mathematical journal
    • /
    • v.25 no.4
    • /
    • pp.425-431
    • /
    • 2009
  • We provide a local convergence analysis for Newton-like methods for the solution of generalized equations in a Banach space setting. Using some ideas of ours introduced in [2] for nonlinear equations we show that under weaker hypotheses and computational cost than in [7] a larger convergence radius and finer error bounds on the distances involved can be obtained.

UNIFYING STATIONARY EQUATIONS FOR GENERALIZED CANONICAL CORRELATION ANALYSIS

  • Kang Hyun-Cheol;Kim Kee-Young
    • Journal of the Korean Statistical Society
    • /
    • v.35 no.2
    • /
    • pp.143-156
    • /
    • 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.