The high-speed rotating superconducting rotor can be used as a sensor to measure angular speed or position. Mass unbalance and oblateness of are the main error sources General Electric company has developed an magnetic suspension device with accuracy 0.005<sup>° </sup>per hour, but its structure is very complex. So it difficult process assemble extremely small mass-unbalance oblaten...

We present a new test for a possible Mach-Sciama dependence of the Gravitational constant G. According to Ernst Mach (1838-1916), the gravitational interaction depends on the distribution of masses in the universe. A corresponding hypothesis of Sciama (1953) on the gravitational constant, c/G = ∑ mi/ri, can be tested since the elliptic earth orbit should then cause minute annual variations in G...

Superconducting stiffness $\rho_s$ and coherence length $\xi$ are usually determined by measuring the penetration depth $\lambda$ of a magnetic field upper critical $H_{c2}$ superconductor (SC), respectively. However, in SC, e.g. some iron-based, this could lead to erroneous results since internal be very different from applied one. To overcome problem Fe$_{1+y}$Se$_x$Te$_{1-x}$ with $x \sim 0....

The detection of broken rotor bars in three-phase squirrel cage induction motors by means of current signature analysis is presented. In order to diagnose faults, a Neural Network approach is used. At first the data of different rotor faults are achieved. The effects of different rotor faults on current spectrum, in comparison with other fault conditions, are investigated via calculating Power ...

A nano coaxial rotor was designed, fabricated and studied experimentally at an ultralow Reynolds number ranging from 5000 to 20,000. The Minimum Induced Loss theory was employed to optimize the geometry of nano coaxial rotor with the introduction of weights to take into account the interference of upper rotor and lower rotor. The chord and twist distributions of both rotors were achieved as a r...

This work deals with effects of asymmetric stiffness on the dynamic behaviour of the rotor system. The analysis is presented through an extended Lagrangian Hamiltonian mechanics on the asymmetric rotor system, where symmetries are broken in terms of the rotor stiffness. The complete dynamics of asymmetries of rotor system is investigated with a case study. In this work, a mathematical model is ...