Purpose: previous studies have suggested that thigh muscle imbalance may be a risk factor for knee injury. The Present study aimed to compare Hamstring-to-Quadriceps (H:Q) Ratio and dynamic stability between the two lower limbs of elderly people. Methods: This was a correlational study and by nonprobability sampling 19 healthy community doweling elderly (age=65.93±3.53 yrs.) p...

in order to determine the stability of underwater robots, their governing differential equations of motion in vertical and horizontal planes should be investigated. for horizontal plane stability, using routh stability criterion, four hydrodynamic coefficients, including derivatives of the lateral force and vertical moment with respect to sway and angular velocity are required. these coefficien...

a chaotic optimization algorithm (coa) based approach for the robust coordinated design of the upfc power oscillation damping controller and the conventional power system stabilizer has been investigated in this paper. chaotic optimization algorithms, which have the features of easy implementation, short execution time and robust mechanisms of escaping from local optimum, is a promising tool fo...

This paper deals with dynamic Stability of single walled carbon nanotube. Strain gradient theory and Euler-Bernouli beam theory are implemented to investigate the dynamic stability of SWCNT embedded in an elastic medium. The equations of motion were derived by Hamilton principle and non-local elasticity approach. The nonlocal parameter accounts for the small-size effects when dealing with nano-...

In this paper, to cope with the stochastic dynamic (or multi-period) problem, two new quadratic assignment-based mathematical models corresponding to the dynamic and static approaches are developed. The product demands are presumed to be dependent uncertain variables with normal distribution having known expectation, variance, and covariance that change from one period to the next one, randomly...

Dynamic slope stability in open-pit mines still remains a challenging task in the computational mining design. Earthquake and blasting are two significant sources of dynamic loads that can cause many damages to open-pit mines in active seismic areas and during exploitation cycles. In this work, the effects of earthquake and blasting on the stability of the NW slope of Chadormalu mine are compar...

Efficiency of numerical methods is an important problem in dynamic nonlinear analyses. It is possible to use of numerical methods such as beta-Newmark in order to investigate the structural response behavior of the dynamic systems under random sea wave loads but because of necessity to analysis the offshore systems for extensive time to fatigue study it is important to use of simple stable meth...