in this paper first we try to analysis the behavior ofthe soas in the optical networks and then have proposed anumerical simple model to simulate the behavior of thesemiconductor optical amplifiers. after that by employing thismodel as inline amplifier for a dwdm optical system, we havesimulated the transmission of 10 channels with bit rate 10 gb/sup to distance 3970 km with rz-dpsk modulation ...

this paper presents a novel control method to improve the efficiency of low-voltage dc-dc converters at light loads. pulse width modulation (pwm) converters have poor efficiencies at light loads, while pulse frequency modulation (pfm) control is more efficient for the same cases. switching losses constitute a major portion of the total power loss at light loads. to decrease the switching losses...

Orexin, mainly produced by orexin-expressing neurons in the lateral hypothalamus (LH), plays an important role in pain modulation. Moreover, it is shown that the nucleus accumbens (NAc) is one of the important areas involved in this modulation. Orexin-1 (OX1) and orexin-2 (OX2) receptors are densely distributed in the NAc. The study investigated the involvement of OX1 receptors in the NAc on an...

Orexin, mainly produced by orexin-expressing neurons in the lateral hypothalamus (LH), plays an important role in pain modulation. Moreover, it is shown that the nucleus accumbens (NAc) is one of the important areas involved in this modulation. Orexin-1 (OX1) and orexin-2 (OX2) receptors are densely distributed in the NAc. The study investigated the involvement of OX1 receptors in the NAc on an...

Static properties, relatively intensity noise and intensity modulation response in quantum cascade lasers (QCLs) studied theoretically in this paper. The present rate equations model consists of three equations for the electrons density in the conduction band and one equation for photons density in cavity length. Two equations were derived to calculate the noise and modulation response. Calcula...

Design and construction of a stable current supply with protection circuits are described. The reported circuit provides a high-stable and high-level current variable from 0.5-1.2 A with the protect ion circuits to prevent over load current, voltage and off-range temperature operation. A detailed analysis of the circuit parameters is given and the time behaviors of the load voltage/current and ...

Introduction: 17β-estradiol modulates nociception by binding to estrogenic receptors and also by allosteric interaction with other membrane-bound receptors like glutamate and GABAA receptors. Beside its autonomic functions, paragigantocellularis lateralis (LPGi) nucleus is also involved in pain modulation. The aim of the current study was to investigate the role of the intracellular estrogen...