the purpose of this research was to assess the influence of several orchard systems involving trees trained to different leader numbers on growth, cropping, and fruit quality of two apple cultivars. the study was conducted during 1994-2007 at the fruit experimental station in samotwór, next to wrocław (south-western poland). one-year-old trees of ‘elstar’ and ‘jonagold’ cultivars on the m.9 roo...

Squeeze Film Dampers (SFD) are commonly used for passive vibration control of rotor-bearing systems. The Magnetorheological (MR) and Electrorheological (ER) fluids in SFDs give a varying damping characteristic to the bearing that can provide active control schemes for the rotor-bearing system. A common way to model an MR bearing is implementing the Bingham plastic model. Adding this model to th...

In this paper, the effectiveness of stiffness and damping of bearing is investigated on the natural frequencies of the rotor-bearing system. The rotor-bearing system consists of a shaft, two bearings and a disk between two bearings. Parallel spring-damper in horizental and vertical directions is considered for modeling the stiffness and damping of bearings. The gyroscopic effect is also conside...

In the recent years, non-connected piled raft foundation has been considered as an economical and practical deep foundation in the situation that high shear and concentrated loads may occur at the connection of the raft and pile head. This paper was presented an experimental study of a square foundation on the effects of parameters such as S/D, L/D and etc. in two cases of connected or non-conn...

introduction: transtibial amputation is the most common amputation in lower limbs. volume loss of residual limb occurs during daily use of prostheses, which results in pistoning between residual limb and prosthetic socket. the goal of this study was to design and fabricate a pneumatic suspension system in transtibial supracondylar prostheses and to evaluate its effect on residual limb pistoning...

Structural walls commonly used as efficient structural elements to resist lateral and vertical loads. Diverse performance of bearing wall system in past earthquakes, motivates investigation on the adequacy of current seismic design provision for these walls. This study considers seismic performance of model walls of bearing wall and building frame systems designed as ordinary and special struct...

This paper presents the effect of preload on nonlinear dynamic behavior of a rigid rotor supported by two-lobe aerodynamic noncircular journal bearing. A finite element method is employed to solve the Reynolds equation in static and dynamical states and the dynamical equations are solved using Runge-Kutta method. To analyze the behavior of the rotor center in the horizontal and vertical directi...

Crack fault of rotor is one of the most prominent problems faced by magnetic bearing rotor system. In order to improve the safety performance of this kind of machinery, it is necessary to research the vibration characteristics of magnetic bearing cracked rotor system. In this paper, the stiffness model of the crack shaft element was established by the strain energy release rate (SERR) theory. T...

Slewing bearing, which is widely applied in tank, excavator and wind turbine, is a critical component of rotational machine. Standard procedure for bearing life calculation and condition assessment was established in general rolling bearings, nevertheless, relatively less literatures, in regard to the health condition assessment of slewing bearing, were published in past. Real time health condi...