Numerical and Experimental Investigation of an Elliptical Paraboloid Shell Model
For practical engineering purpose, a new flat shell element baptized (ACM_Q4SBE1) is presented in this paper. The formulated element can be used for the analysis of thin shell structures; no matter how the geometrical shape might be. Tests on standard problems have been examined. Since, the analysis of thin shell structures has generally been purely carried out on a theoretical basis; it is of importance to present some experimental results of an elliptical paraboloid under uniformly distributed load pressure. The results obtained from both numerical and experimental work are presented. Index Terms— Elliptical Paraboloid, finite element, flat shell element.
Matrix Displacement Analysis of Anisotropic Shells by Triangular Elements
Over the last five years or so both in the USA (especially by the active group at Berkeley under R. W. Clough(7) ) and the UK, there have been a number of attempts to incorporate the plane triangular element under bending and membrane action into a general matrix displacement analysis of shells. All investigators stressed the positive aspects of the triangular element, which arise from its adaptability to any geometrical form of the shell, but noted at the same time some serious shortcomings due to a partial satisfaction of the kinematic compatibility conditions at the boundary. Thus we have within the Matrix Displacement Method the rather unusual example of a type of element whose deficiency with respect to kinematic compatibility does not automatically ensure convergence to the exact result as the number of elements is increased.
The Intuitive Physics of the Equilibrium of the Lever and of the Hydraulic Pressures: Implications for the Teaching of Elementary Physics.
The research field of intuitive physics focuses on discrepancies between 
theoretical and intuitive physical knowledge. Consideration of these 
discrepancies can help in the teaching of elementary physics. However, 
evidence shows that theoretical and intuitive physical knowledge may also 
be congruent. Physics teaching could further benefit from understanding the 
reasons for this congruence. The present study explored these reasons by 
investigating the intuitive physics of the equilibrium of the lever and of the 
hydraulic pressures. It was found that the intuitive-physics law of the lever 
was multiplicative for all participants while the intuitive-physics law of the 
hydraulic pressures differed among participants. Since these laws are 
equally simple and the layman probably has had extensive experience with 
the lever and scarce or no experience with the hydraulic lift, these findings 
support the general hypothesis that physical laws and corresponding 
intuitive-physics laws are congruent when people have had experience with 
the respective phenomena. The results and theoretical considerations suggest 
two strategic principles for teaching elementary physics.