Abstract Multi-layered composite shells are extensively used in many industrial fields since they have superior performance applications. As load-carrying components, buckling failure is one of the most common modes multi-layered shells. Hence, layup design based on optimal factors widely concerned, where lamination parameters commonly representation stiffness. However, formulations laminate st...

the classical test theory (ctt) and item response theory (irt) are widely used in construction and analysis of exams and questionnaires. because of the various shortcomings of ctt, irt has been designed. even though irt has overcome most of the limitations of ctt and has made computer adaptive testing possible, it is still important to point out that not enough reasons exist to totally discard ...

This report describes a semi-physical model for the dimensional stability properties (i.e. curl) of the carton board produced at AssiDomän Frövi, Sweden. The main equations are based on classical lamination theory of composite materials, and each constituent ply is considered as a macroscopic homogeneous, elastic medium. The model used data from February to June 2001, and show a general agreeme...

We investigate the formation of microscopic patterns in a copper single crystal deformed in a shear experiment. Using high-resolution electron backscatter diffraction (EBSD) imaging, we find a band-like microstructure consisting of confined areas in the sample with rotated lattice. Digital image correlation (DIC) allows us to exactly determine the macroscopic state of deformation of the sample....

The framework of aane and hyperbolic laminations provides a unifying foundation for many aspects of conformal dynamics and hyperbolic geometry. The central objects of this approach are an aane Riemann surface lamination A and the associated hyperbolic 3-lamination H endowed with an action of a discrete group of iso-morphisms. This action is properly discontinuous on H, which allows one to pass ...

In this paper, the optimum weight and cost of a laminated composite plate is seeked, while it undergoes the heaviest load prior to a complete failure. Various failure criteria are defined for such structures in the literature. In this work, the Tsai-Hill theory is used as the failure criterion. The theory of analysis was based on the Classical Lamination Theory (CLT). A newly type of Genetic Al...

topological analysis has been performed on the total electron density of the two forms of ozonemolecule,c2v and d3h ,to investigate the nature of chemical bonds ,molecular structure , atomiccharges and electrical properties. while these concepts have been completely discussed usingclassical models the emphasize in this work is based on quantum theory of atoms in molecules(qtaim). because the d3...

The thermal buckling response of square plates with variable angle tows under simply supported conditions is modeled numerically. path tow as a function lateral location. classical lamination theory utilizes fiber paths to calculate loads and stiffness matrices. Using Kirchhoff plate finite element theory, the global material matrix geometric are obtained. By using these matrices, eigenvalues o...

In this paper, the optimum weight and cost of a laminated composite plate is seeked, while it undergoes the heaviest load prior to a complete failure. Various failure criteria are defined for such structures in the literature. In this work, the TsaiHill theory is used as the failure criterion. The theory of analysis was based on the Classical Lamination Theory (CLT). A newly type of Genetic Alg...