Several types of power quality problems can be observed in network. These include voltage unbalance, flicker, sags and swells, interruptions, current harmonics. Voltage sag is one the vital issues. This problem cause a decrease grid over short time horizon. The aforementioned caused by various circuits widespread use sensitive devices. have significant impact on systems. In this review article,...

We aimed to noninvasively estimate the relative contribution of the cone photoreceptors to the photopic flicker electroretinogram (ERG) in humans. Responses to ganzfeld square-wave flicker (15, 30, and 60 Hz) were recorded in the presence of a rod-saturating background. We used a modified paired flash technique in which a bright probe flash was presented at different times during a flicker cycl...

detection & classification of power quality (pq) disturbances are the most important problems in distribution systems. in this paper, a new approach for the detection and classification of single and combined pq disturbances is proposed which utilizes fuzzy logic and particle swarm optimization (pso) algorithms. in this approach, first suitable features of the waveform of pq disturbances ar...

The system stability is greatly hampered when green electricity is feed into the conventional electricity network due to intermittent nature of renewable sources. The electricity generation from wind so far predominates than that of other renewable sources. In order to maintain system stability of the electricity network, IEC-61400 (International Electro-technical Commission) standard has defin...

The power quality issue will take new dimension due to power system restructuring and shifting trend towards distributed generation. Huge loss in terms of time and money have made power quality problems a major anxiety for modern industries with non-linear loads in electrical power system. Power quality consists of a large number of disturbances such as voltage sags, swells, harmonics, notch, f...

The detection and classification of power quality disturbances in power systems are important tasks in monitoring and protection of power system network. Most of the power system disturbances are non stationary and transitory in nature and new tools are being used nowadays for the analysis of power quality disturbances. This paper presents a wavelet based feature extraction method for the detec...

A 5.2-GHz CMOS receiver employs a double downconversion heterodyne architecture with a local oscillator frequency of 2.6 GHz and applies offset cancellation to the baseband amplifiers. Placing the image around the zero frequency, the receiver achieves an image rejection of 62 dB with no external components while minimizing the flicker noise upconversion in the first mixing operation. Realized i...

We have investigated noise characteristics of novel GaN/Al0:15Ga0:85N doped channel heterostructure field effect transistors designed for high-power density applications. The measurements were carried out for various gate bias VGS and the drain voltage VDS varying from the linear to the saturation regions of operation VDS > 5 V. Our results show that flicker, e.g., 1=f noise, is the dominant li...

Purpose To mathematically model the temporal dynamic responses of retinal vessel diameter (D), oxygen saturation (SO2), and inner retinal oxygen extraction fraction (OEF) to light flicker and to describe their responses to its cessation in humans. Methods In 16 healthy subjects (age: 60 ± 12 years), retinal oximetry was performed before, during, and after light flicker stimulation. At each ti...

The sun-fish Lepomis responds to a moving system of stripes by a motion of its body. By changing the velocity of motion of the stripe system different flicker frequencies can be produced and thus the relation of flicker frequency to critical intensity of illumination can be studied. Threshold illumination varies with flicker frequency in such a way that with increasing flicker frequency the int...