background: developmental dysplasia of hip (ddh) is a common childhood disorder, and ultrasonography examination is routinely used for screening purposes. in this study, we aimed to evaluate a modified combined static and dynamic   ultrasound technique for the detection of ddh and to compare with the results of static and dynamic ultrasound techniques.       methods: in this cross-sectional stu...

in methods presented to calculate the voltage collapse point, the transmission system is usually the only part of the power system that is completely modeled. distribution systems are often replaced by aggregate load models because the use of the detailed model of distribution systems in voltage stability analysis not only increases the computation time, but also decreases the probability of co...

Arch dams are generally built in cantilvever monoliths. Vertical contraction joints between monoliths control the stresses due to concrete shrinkage and temperature variations. Past studies in earthquake safety evaluation of the system often show the tensile fracture and local nonlinear deformation of joints. In this paper, some nonlinear joint element constitutive models are presented to exami...

in the conventional design and analysis methods affecting parameters (loads, materials'strength, etc) are not set as probable variables. safety factors in the current codes andstandards are usually obtained on the basis of judgment and experience, which may beimproper or uneconomical. in technical literature, a method based on nonlinear static analysisis suggested to set reliability index on st...

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...

this paper describes a modified structural dynamics model for aeroelastic analysis of high-aspect-ratio wings undergoing large deformation behavior. to gain this aim, a moderate deflection beam model is modified with some important large deflection terms and then coupled with a state space unsteady aerodynamics model. finite element method is used to discretize the equations of motion. a dynami...

arch dams are generally built in cantilvever monoliths. vertical contraction joints between monoliths control the stresses due to concrete shrinkage and temperature variations. past studies in earthquake safety evaluation of the system often show the tensile fracture and local nonlinear deformation of joints. in this paper, some nonlinear joint element constitutive models are presented to exami...

This paper deals with the effect of the intrinsic material length-scale parameter on the stability and natural frequency of a rectangular micro-plate for two different cases; fully clamped and fully simply supported. A variational formulation based on Hamilton’s principle and the modified couple stress theory is used to obtain the nonlinear governing equation of a micro-plate incorporating the ...