the harmony search algorithm is applied to optimum designs of a functionally graded (fg)-carbon naotubes (cnts)-reinforced pipes conveying fluid subjected to moving load. the structure is modeled by reddy cylindrical shell theory and the motion equations are derived by hamilton's principal. based on differential quadrature method (dqm), the dynamic displacement of system is derived. the le...

this study involved the development and evaluation of a new filtering technique, as based on adaptive free mass load cell. the technique's application in reduction of vibration and impulse noise (commonly added to the sugar cane harvester yield monitoring signals) was tested. this technique is based upon assimilate spring- mass vibration system of weighing scale with a free mass load cell ...

Transversal vibrations of an axially moving string under boundary damping are investigated. Mathematically, it represents a homogenous linear partial differential equation subject to nonhomogeneous boundary conditions. The string is moving with a relatively (low) constant speed, which is considered to be positive.  The string is kept fixed at the first end, while the other end is tied with the ...

springs are the  mechanical parts which have many application in industries. static and dynamic forces cause relaxation in these parts so that they lose some of their free length and reaction force. springs constant are very important in airplane and vailway industry since constant and variable forces are applied to them in period time, therefore it is necessary to avoid decreasing in spring co...

Generally, the flexible robot system can be modeled as the two-mass system which consists of a motor and load connected by a spring. Thus, its elasticity causes resonance in the system. By using the conventional PID controller, this method cannot perform well in this situation. Much research has proceeded with the aim of reducing vibration. A new effective control method, the resonance ratio co...

We investigate the dynamics of the vertically forced Duffing oscillator with suspended tuned mass absorber. Three different types of tuned mass absorbers are taken into consideration, i.e., classical single pendulum, dual pendulum and pendulum-spring. We numerically adjust parameters of absorbers to obtain the best damping properties with the lowest mass of attached system. The modification of ...

The vibrations produced by trains include two parts which are deterministic and random vibrations. Due to variation of dynamic loads and patterns of load-time, the random vibration of moving train is one of the most important issues in the field of railway engineering. One of the important sources in producing the train vibrations is rail roughness and irregularities. In this paper, responses o...

The Wilberforce pendulum provides an important qualitative demonstration of coupled harmonic oscillators, but quantitative measurements are not typically performed. The present work examines the dynamics of a simple pendulum comprising a steel spring with attached mass using an ultrasonic motion detector. A series of measurements allowed determination of the coupling constant between the longit...

In this article, in reference to the modified couple stress theory and Euler-Bernoulli beam theory, the free lateral vibration response of a micro-beam carrying a moveable attached mass is investigated. This is a decent model for biological and biomedical applications beneficial to the early-stage diagnosis of diseases and malfunctions of human body organs and enzymes. The micro-cantilever beam...