In this paper, we investigate the effects of auto-tracking subsystem together with different beam divergences on SNR, BER and stability of FSO communication links. For this purpose we compute the values of power, SNR and BER on receiver, based on analytic formula of Gaussian beam on receiver plane. In this computation the atmospheric effects including absorption, scattering and turbulence are c...

In this paper, we generalize and refine some Berezin number inequalities for Hilbert space operators. Namely, the Hermite-Hadamard inequality other recent results by using concept of superquadraticity convexity. Then extend these number. Among inequalities, it is shown that if S, T ? L(H(?)) such ber(T) ber(|S|) f a nonnegative superquadratic function, then (ber (T)) ber(f (|S|)) ?ber (f (||S| ...

The effects of aberration on the Bit-Error-Rate (BER) and reliability of free- space optical (FSO) communication links are investigated. Based on aberrated divergent rectangular partially coherent flat-topped beam formula on the receiver plane and considering the atmosphere losses due to absorption and scattering, numerical values for Power In Bucket (PIB), Signal to Noise Ratio (SNR) and BER a...

This paper demonstrates the design of an Arrayed Waveguide Gratings (AWG) based optical switch. In the design both physical and network layer analysis is performed. The physical layer power and noise analysis is done to obtain Bit Error Rate (BER). This has been found that at the higher bit rates, BER is not affected with number of buffer modules. Network layer analysis is done to obtain perfor...

background: restoration of anterior primary teeth with severe caries lesion is a big challenge. the aim of this study was to compare the fracture resistance of three types of post, including composite resin, customized quartz fi ber and prefabricated glass fi ber in restoration of severely damaged primary anterior teeth. materials and methods: sixty extracted human primary maxillary incisors we...

this study investigated the effect of berberine on the hepatic dysfunction and histological damage induced by renal ischaemia/ reperfusion (i/r) at an early stage. there were four groups (n=7). in ber+i/r group, rats received berberine (ber; 15 mg/kg/day) orally for 7 days before induction of ischemia. i/r group received distilled water orally for 7 days. in sham and ber+sham groups in which ar...

This research was carried out to figure the effect of chemical treatments hazelnut shell powders (HSPs) on elastic properties, ultrasonic wave velocities, and damping properties bio-based epoxy resin (BER) biocomposites. Natural shells (HSs) were chemically treated using sodium hydroxide (NaOH), acetic anhydride (AA). Then, HSs that with NaOH AA, not subjected treatment ground obtain HSPs. The ...

In future high-speed self-routing photonic networks based on all-optical time division multiplexing (OTDM) it is highly desirable to carry out packet switching, clock recovery and demultplexing in the optical domain in order to avoid the bottleneck due to the optoelectronics conversion. In this paper we propose a self-routing OTDM node structure composed of an all-optical router and demultiplex...