this paper consists of three sections. in the first section an efficient method is used for decomposition of the canonical matrices associated with repetitive structures. to this end, cylindrical coordinate system, as well as a special numbering scheme were employed. in the second section, divide and conquer method have been used for eigensolution of these structures, where the matrices are in ...

in this paper, we study fuzzy substructures in connection withhv-structures. the original idea comes from geometry, especially from thetwo dimensional euclidean vector space. using parameters, we obtain a largenumber of hyperstructures of the group-like or ring-like types. we connect,also, the mentioned hyperstructures with the theta-operations to obtain morestrict hyperstructures, as hv-groups...

an attempt has been made to explore the general trends in the seismic response of planasymmetric structures when subjected to near-fault and far-fault ground motions. systems with structural wall elements in both orthogonal directions considering actual and common nonlinear behavior under bi-directional excitation were studied. idealized single-storey models with uni-axial eccentricity were emp...

cycloaddition reaction between c30 and hula-i, 3-diene was studied within the snimework of am i (rhf)level. the reaction involving the double bond between two hexagons and a hexagon and a pentagon, as wellas the cycloaddition products followed by disrotatory ogs s electrocyclic ring openings were considered.thermodynamics parameters and stability energy and innsation state are evaluated in thre...

chemical vapor deposition was employed to synthesize carbon nanotubes with ni-loaded mcm-41 and mcm-48 as catalysts and acetylene as precursor at 750°c. mesoporous ni mcm-41 and ni mcm-48 molecular sieves were synthesized by a hydrothermal method and were characterized by xrd and n2 adsorption isotherm. the catalytically synthesized carbon materials were characterized with raman spectroscopy, n...

we propose a new generation of unbiased (bias-free) antenna-less cw thz photomixer emitters array made of asymmetric msm gratings with subwavelength pitch, operating in optical near-field regime. we take advantage of the size effects in near-field optics and electrostatics to demonstrate the possibility of enhancing the thz power by four orders of magnitude, as compared with a similar array of ...

in this paper effect of pile-soil consideration in obtaining seismic response offshore structure is assessed due to earthquake loading. inducedseismic force is one of the most important excitations for the dynamic response of an offshore structure. according to api, seismic forces should be accounted in platform design for seismically active regions in order to determine the allowable seismic r...

In this article the notions of semi weak orthogonality and semi weak factorization structure in a category $mathcal X$ are introduced. Then the relationship between semi weak factorization structures and quasi right (left) and weak factorization structures is given. The main result is a characterization of semi weak orthogonality, factorization of morphisms, and semi weak factorization structur...