Walking is a state of unbalanced body. Not to fall down, it takes a way. Technology is another state of progress depending unbalanced structures of human functions and relations. In balanced societies and cultures which are being considered as technologically primitive, what we see is lack of technology, but a state of balance and order. It is not surprising to see that great technological deve...

This paper investigates an improved control strategy for a doubly-fed induction generator (DFIG) based wind-power generation system with series grid-side converter (SGSC) under network unbalance and harmonic grid voltage distortion conditions. The integrated mathematical modeling of the DFIG system with SGSC is established by taking both the negative-sequence and harmonic components of the grid...

This work presents a technique that allows the calibration of mathematical models in rotating systems. The method is based on the application of a hybrid meta-heuristic search, which employs genetic algorithm and simulated annealing. The capabilities of the method are evaluated by means of experimental results obtained in the test-rig of Politecnico di Milano. The experimental set up consists o...

This work analyzes the behavior of surface-mounted permanent magnet synchronous motors (SPMSMs) operating under stator faults. The studied faults are resistive unbalance and winding inter-turn short circuits, which may lead to unbalanced conditions of the motor. Both faults may reduce motor efficiency and performance and produce premature ageing. This work develops an analytical model of the mo...

The smart grid and micro-grid technologies are playing necessary role in power system due to their benefi ts over traditional utility grid system. In micro grid, control and management has many functions to keep up stability and to boost power quality of the system. In this paper, a hierarchical control is presented which incorporates primary, secondary and tertiary control levels are planned f...

We present a simple combining receiver for a dual-diversity wireless relay network. The main concern of the paper is to face the trade-off between performance and complexity. The receiver focuses on signal-to-noise ratio (SNR) monitoring and selects dynamically between selection combining (SC) and equal gain combining (EGC) depending on the SNR ratio of the two received branches. It is shown th...

In the literature, Spherobot refers to a mobile robot with a spherical exo-skeleton and a propulsion mechanism that uses unbalance masses in a tetrahedral arrangement. A modified design of Spherobot, that is better suited to fabrication, is presented in this paper. The modified propulsion mechanism and other components of the design are discussed in detail to highlight the challenges of fabrica...

BACKGROUND Myocardial depression in sepsis is common, and it is associated with higher mortality. In recent years, the hypothesis that the myocardial dysfunction during sepsis could be mediated by ischemia related to decreased coronary blood flow waned and a complex mechanism was invoked to explain cardiac dysfunction in sepsis. Oxidative stress unbalance is thought to play a critical role in t...

In order to reduce the mass, the new designs of turbojet engines use rotors working with higher speeds. These rotors are subjected to large unbalance during engine operational conditions. An additional damping might be necessary in order to enable working at rotation speeds higher than the critical ones. In order to achieve this objective, Integral S-shaped Squeeze Film Damper (ISSFD) and Multi...

Availability of quality power has become an important issue for industrial utilities due to frequent performance variations in process industries. Increase in the generating capacity has not kept up pace of power demand, which results into shortage of power supply and power system network is normally subjected to varying and unequal loads across the three phases. Continuous variation of single-...