One of the important issues in the study of steel frames is to find a suitable formulation for semi-rigid connections. In this paper, the explicit stiffness matrix for a two-dimensional beam-column element having end-flexibilities is derived. The effects of the lateral uniformly distributed load on the deflection are considered. Both tensile and compressive axial loads are also taken into accou...

How must n equal circles of given radius be placed so that they cover as great a part of the area of the unit circle as possible? To analyse this mathematical problem, mechanical models are introduced. A generalized tensegrity structure is associated with a maximum area configuration of the n circles, whose equilibrium configuration is determined numerically with the method of dynamic relaxatio...

Hydrogels are widely used as in vitro culture models to mimic 3D cellular microenvironments. The stiffness of the extracellular matrix is known to influence cell phenotype, inspiring work toward unraveling the role of stiffness on cell behavior using hydrogels. However, in many biological processes such as embryonic development, wound healing, and tumorigenesis, the microenvironment is highly d...

A Newtonian (vectorial) approach is used to develop the governing differential equations of motion for a three layer sandwich beam in which the uniform distribution of mass and stiffness is dealt with exactly. The model allows for each layer of material to be of unequal thickness and the effects of coupled bending and longitudinal motion are accounted for. This results in an eighth order ordina...

A finite element solution based on equevalent elements is proposed for the static and dynamic analysis of tallhigh tensioned cable antennas. To reduce high number of degrees of freedom in space frame body of a structure, a simple equivalent beam element is defined for each simulative substructure. This numerical procedure is applicable to analyze complex three dimensional assemblies of substruc...

B = signed Boolean matrix C = damping matrix f = vector of external forces G = matrix of associated modes g = vector of connecting forces K = stiffness matrix L = Boolean localization matrix M = mass matrix q = vector of unique degrees of freedom R = reduction matrix r = vector of residual forces t = time u = vector of degrees of freedom Y = receptance matrix Z = dynamic stiffness matrix = vect...