In this paper, the general governing equations of three-dimensional vibrations of an Euler-Bernoulli Beam under influences of system dynamics are derived by the Hamiltonian method. Then two fundamental cases of a cantilever beam and a rotating beam are considered. The conventional methods for vibration suppression debit to expenses and make new problems such as control spillover because they ar...

development of ultrasound technique has not been progressing for evaluating the internal quality of fruits as fast as that of processed foods. in this research for quality assessment of pear fruit (shah miveh variety) an ultrasonic measurement system was constructed to transmit and receive the ultrasonic waves. the apparatus included a pulser-receiver, a pair of 75 khz ultrasonic transducers wi...

The article presents the results of development works and research on atomization process carried out using two prototype high-power ultrasonic systems. Ultrasonic systems have been designed to develop a new metal powder production process; these materials are increasingly used in modern manufacturing processes such as additive technologies or spraying surfacing processes. preliminary studies p...

Abstract This paper presents a new design approach for two main components of an ultrasonic plastic welding machine, booster and horn, based on analytical model. The procedure is developed due to the lack comprehensive precise model rapid analysis these components. previous models use one-dimensional wave equation that causes significant errors in designing with large lateral dimensions. Three-...

air spindles are one of the main elements of precise machine tools. vibration of these spindles is one of the vital issues necessary for investigation. among parameters which influence air spindle vibrations are rotational speed, compression air method, input nozzle diameter, air gap pressure. in this study using ansys, the effects of air gap thickness on air spindle vibrations have been invest...

This paper is based on material presented at the start of a Health Protection Agency meeting on ultrasound and infrasound. In answering the question 'what is ultrasound?', it shows that the simple description of a wave which transports mechanical energy through the local vibration of particles at frequencies of 20 kHz or more, with no net transport of the particles themselves, can in every resp...

the evaluation and control of the trains induced vibrations needs even more attention in the case of underground tracks which passes near to monuments and historical sites. the rail corrugations which occur due to the wheels’ impulse loads during the operation period of underground railway tracks, usually amplify the ground borne noise and vibration. in the current study, the mentioned phenomen...

Piezoelectric bone surgery, known simply as piezosurgery, is a new technique of osteotomy and osteoplasty, which requires the use of microvibrations of ultrasonic frequency scalpels. The principle of piezosurgery is ultrasonic transduction, obtained by piezoelectric ceramic contraction and expansion. The vibrations thus obtained are amplified and transferred onto the insert of a drill which, wh...

W H E N cells of amphibian embryos differentiate they begin to synthesize the structural proteins characteristic of the cell type, and this is immediately preceded by the beginning of the absorption of the yolk platelets. These events may be studied in cultured cells (Jones & Elsdale, 1963) or in sections of fixed embryos. When amphibian platelets are utilized by the cell, they undergo certain ...

We propose a method of driving the vibrations of normal modes of a target molecule into coherence using stimulated Raman scattering. In concert many vibrations can produce a larger anti-Stokes signal than a single vibration. The same illumination does not drive other molecules to have coherent vibrations so that these molecules produce a weaker signal. We investigate how target and confounder m...