exposure to vibration is the cause of some occupational injuries and diseases. objective of this study was determination of vibration exposure of tractor drivers and assessment of musculoskeletal disorder . this cross-sectional and descriptive- analytical study was administrated to 95 tractor drivers to census method and measuring induced vibration to the drivers was done in three axis, x, y, a...

In this paper, we propose a new numerical method for determining a moving boundary from Cauchy data in one dimensional heat equation. The numerical scheme is based on the use of fundamental solutions of the heat equation as basis functions. In order to regularize the ill-conditioned linear system of equations resulted by collocating boundary data, we apply successfully the Tikhonov regularizati...

Non-linear reaction-diffusion processes with cross-diffusion in two-dimensional, anisotropic media are analyzed by means of an implicit, iterative, time-linearized approximate factorization technique as functions of the anisotropy of the heat and species diffusivity tensors, the Soret and Dufour cross-diffusion effects, and five types of boundary conditions. It is shown that anisotropy and cros...

A generalization of vector fields, referred to as N -direction fields or cross fields when N = 4, has been recently introduced and studied for geometry processing, with applications in quadrilateral (quad) meshing, texture mapping, and parameterization. We make the observation that cross field design for two-dimensional quad meshing is related to the well-known GinzburgLandau problem from mathe...

We use an expanded variational approach based on dissipation to study the motion of the boundary of a non-circular cylindrical, and thus essentially 2-dimensional, crystalline grain of arbitrary cross-section enclosed in another grain of the same material under conditions where the normal grain boundary motion is coupled to relative tangential motion of the grains along the grain boundary. Coup...

Water flow in open channels is always subject to the resistance to flow and energy dissipation. For design purposes, one of the needed variables is the hydraulic resistance coefficient. For this mean, the influence of cross-sectional shape together with secondary flow cells and lateral distribution of true boundary shear stress have not yet been fully explored. This paper surveys the number of ...

Abstract:   The theory of optimization has improved remarkably during the last four decades. The main part of optimizing investigations has been focused on enhancing buckling resistance which does not violate the economic feasibility of final design. The finite element analysis which is called ESO (Evolutionary Structural Optimization) is presented for optimum (or most ideal) design of c...

In this paper, a method based on Chebyshev polynomials is developed for examination of geometrically nonlinear behaviour of thin rectangular composite laminated plates under end-shortening strain. Different boundary conditions and lay-up configurations are investigated and classical laminated plate theory is used for developing the equilibrium equations. The equilibrium equations are solved dir...