Adaptive-passive vibration and acoustic control systems can provide significant attenuation without requiring significant power compared to an active control system. The control system includes an algorithm to evaluate a costfunction to be minimised, which is typically a time-averaged multiplication of the vibration or noise on the resonator and at a point in the system where the disturbance is...

In this paper, a fractional-order extension of negative position feedback (NPF) controller for active damping is proposed. The design the motivated by frequency-domain loop shaping analysis, and dynamics are defined to maintain high-pass characteristics an integer-order NPF. proposed provides greater attenuation resonance peak flexible plant than integer order equivalent with same high-frequenc...

The aim is to develop vibration control of flexible spacecraft by adaptive controller. A case study will be carried out which simulates planar motion of flexible spacecraft as a coupled hybrid dynamics of rigid body motion and the flexible arm vibration. The notch filter and adaptive vibration controller, which updates filter and controller parameters continuously from the sensor measurement, a...

In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth’s atmosphere. Based on statistical rain rates data for Bulgaria, the link...

In this paper, the link quality in SHF and EHF ranges are studied. In order to achieve high data rate higher frequencies must be used – centimeter waves (SHF), millimeter waves (EHF) or optical range. However, there are significant problem when a radio link work in that diapason – rain attenuation and attenuation in earth’s atmosphere. Based on statistical rain rates data for Bulgaria, the link...

Hepatic steatosis assessment is of paramount importance for living liver donor selection because significant hepatic steatosis can affect the postoperative outcome of recipients and the safety of the donor. The validity of various noninvasive imaging methods to assess hepatic steatosis remains controversial. The purpose of our study is to investigate the association between noninvasive imaging ...

In machining industries, achieving better surface finish of a product is very essential. Surface finish is important in terms of tolerances, it reduces assembly time in mating surfaces which results in overall cost reduction. In this work, three cutting speeds, three feed rates and three depth of cuts were used in boring operation. During the boring operation, the accelerometer was fixed on the...

This article concerned with the translation of Quranic verses to Braille symbols, by using Visual basic program. The system has the ability to translate the special vibration for the Quran. This study limited for the (Noun + Scoon) vibrations. It builds on an existing translation system that combines a finite state machine with left and right context matching and a set of translation rules. Thi...