as there is a rapid growth both in the number of power consumers and also the limitations energy resources, it is clearly accepted that the old version of power grid must change into smart grid from head to toe. one of the most important advantages of smart grid which makes it much more exclusive rather than other typical systems is the two-way connectivity between the utility and the costumers...

the frequency response analysis (fra) test has been recognized as one of the sensitive tools available for detecting electrical and mechanical faults inside power transformers. however, there is still no universally systematic interpretation technique for these tests. many research efforts have employed different statistical criteria in order to aid the interpretative capability of the fra, but...

frequency response analysis (fra) is popular technique which has been used since the last decade as a diagnostic method for transformers. however, accurate interpretation of fra measurements is still challenging. recent studies reveal that apart from winding deformation, fra data can also be influenced by moisture variation in transformer paper insulation. hence, a specific transformer’s model ...

in the present paper, the aeroelastic stability of helicopter rotor blade is determined using aeroelastic frequency response function. the aeroelastic model of blade is obtained by combining dowell - hodges beam model with loewy unsteady aerodynamic theory which considers an unsteady wake beneath the rotor. equations are formed and aeroelastic frequency response functions are obtained by invert...

email marketing is increasingly recognized as an effective internet marketing tool. in this study, a questionnaire is constructed and distributed to a sample of 146 prospects of aditi technologies to find the factors associated with higher response rates. the collected data is analyzed using factor analysis and the 11 factors, from line, subject line, personalization of the subject line, timing...

Many of nonlinear systems in the field of engineering such as nano-resonator and atomic force microscope can be modeled based on Duffing equation. Analytical frequency response of this system helps us analyze different interesting nonlinear behaviors appearing in its response due to its rich dynamics. In this paper, the general form of Duffing equation with cubic nonlinearity as well as par...

In this study, the method of multiple scales is used to perform a nonlinear vibration analysis of a mechanical system in two cases; with dry and lubricated clearance joints. In the dry contact case, the Lankarani-Nikravesh model is used to represent the contact force between the joined bodies. The surface elasticity is modeled as a nonlinear spring-damper element. Primary resonance is discussed...

The effect of frequency content on the dynamic response of concrete gravity dams is investigated in this paper. Dams are one of the most complex structures to handle when there is dynamic analysis involved. One of the influential parameters on these structureschr('39') seismic response is the frequency content of the earthquakes. An index to represent frequency content, which represents frequen...