g e y w o r d s N o n a n t o n o m o u s equation, Wave equation, Uniform attractor, Exponential attractor, a-contraction, Squeezing property. 1 . I N T R O D U C T I O N In this note, we s tudy the long t ime behavior of a general wave equat ion of the form Pu" + Qu' + Au + F (t, u) = h (t) , (1.1) in a Hilbert space H, where A, P , and Q are linear positive self-adjoint operators. This class...

In Analog circuit design field, current reference circuit is mostly used for constant current supply to the circuits, so that their function runs properly. This work gives a circuit that operates with minimum operating voltage and current, CMOS current generator circuit and presents its performance with circuit simulation in 180nm UMC CMOS technology. The designed circuit has four sub parts sta...

Introduction: Well type ionization chamber is a measuring device which is used to determine the activity of brachytherapy sources. The chamber has a cylindrical volume in which a cylindrical tube is mounted in the middle of the chamber. For the measurements, the brachytherapy sources are transferred to the middle of the tube. Materials and Methods: For designing the well type chamber, the measu...

in recent years, there has been a fast growth in wind energy conversion system (wecs). there are two general types of wind turbines in wecs: fixed speed wind turbines and varying speed wind turbines.permanent magnet synchronous generator (pmsg) is one of the most attractive generators for the varying speed turbine wecs.in this paper, a fuzzy controller is proposed to control the current source ...

The current sources which are normally used in research laboratories are not suitable for low noise measurement systems because of the unacceptable level of low frequency noise which they introduce in the measurement chain. The most important source of low frequency noise in such instruments is the solid state device (usually a Zener diode) which is used as voltage reference. By using a novel c...

Because the power systemload the randomness of the nature, power transmission of AC induction system has the low efficiency. In order to improve the transmission efficiency,the transmission efficiency influenced factors of the system is analyzed. Based on the current source power transfer system, DC/DC circuit for dynamic adjustment method is proposed. The method ensures that the transmission e...

introduction: well type ionization chamber is a measuring device which is used to determine the activity of brachytherapy sources. the chamber has a cylindrical volume in which a cylindrical tube is mounted in the middle of the chamber. for the measurements, the brachytherapy sources are transferred to the middle of the tube. materials and methods: for designing the well type chamber, the measu...

This paper proposes a novel topology of multilevel current source inverter which is suitable to apply in low/medium voltage. The proposed topology is capable of producing desirable bidirectional output current levels. Furthermore, it can employ symmetrical DC current sources as well as asymmetrical ones which is a significant advantage. Asymmetrical mode makes it possible to generate a great nu...

Resting frontal electroencephalographic (EEG) asymmetry has been hypothesized as a marker of risk for major depressive disorder (MDD), but the extant literature is based predominately on female samples. Resting frontal asymmetry was assessed on 4 occasions within a 2-week period in 306 individuals aged 18-34 (31% male) with (n = 143) and without (n = 163) lifetime MDD as defined by the Diagnost...