the sofeh mountain in the south of isfahan (iran) has a development of shafts (vertical cave). simorgh cave with a depth of 42 m and a length of 52 m has developed along significant fault structures. structural analysis indicates relationships of orientation between the faults and fractures and shafts and chambers geometries. considering the main ne-sw trend of tectonic structures in the area, ...

In this study, two-dimensional electro-mechanical analysis of a composite rotating shaft subjected to non-axisymmetric internal pressure and applied voltage is investigated where hollow piezoelectric shaft reinforced by boron nitride nanotubes (BNNTs). Composite structure is modeled based on piezoelectric fiber reinforced composite (PFRC) theory and a representative volume element has been cons...

Dynamic behavior of a circular shaft with geometrical nonlinearity and constant spin, subjected to periodic axial load is investigated. The case of parametric combination resonance is studied. Extension of shaft center line is the source of nonlinearity. The shaft has gyroscopic effect and rotary inertia but shear deformation is neglected. The equations of motion are derived by extended Hamilto...

High-voltage circuit breakers are mechanical switching devices which connect and break current circuits (operating currents and fault currents) and carry the nominal current in closed position. As a result of multi-running, the shaft sleeve in operation mechanism could slip and even strip from the shaft at the hinge joint, which decreases the system reliability. In this work, investigations on ...

Analysis of genotypes for genetic predisposition of diseases has profound and widespread clinical application and has become a fundamental tool in the study of molecular epidemiology. In this study, we report a convenient and completely noninvasive approach to perform genotyping using terminal cephalic hair shaft. The average and median DNA amounts purified from the hair shaft are 112 180 (1 SD...

-In the present work an attempt is made to evaluate the suitability of composite material such as E-Glass/Epoxy and HMCarbon/Epoxy for the purpose of automotive transmission applications. A one-piece composite drive shaft for automobile is designed and analyzed using ANSYS software respectively for E-Glass/ Epoxy and HM-Carbon/Epoxy composites with the objective of minimization of weight of the...

Guaranteeing transaction semantics in a highly available and fault tolerant manner is desirable to application developers. Besides, it is a very valuable feature for database-backed applications. SHAFT is a pessimistic concurrency control protocol for partitioned and replicated data, which can be distributed across multiple datacenters. Laying its basis on the Paxos algorithm, the SHAFT protoco...

The aim of this study was to quantify and explain the effect of shaft stiffness on the dynamics of golf drives. Twenty golfers performed swings with two clubs designed to differ only in shaft bending stiffness. Wrist kinematics and clubhead presentation to the ball were determined using optical motion capture systems in conjunction with a radar device for capturing ball speed, launch angle, and...

The torsional stress is caused by interaction between electrical transient air-gap torque by electrical disturbances and mechanical torque of turbine-generator shaft system. If a transient shaft torque exceeds a certain threshold, the loss of fatigue life occurs and in the end it is possible to happen shaft failure. This paper discusses that which factors can damage to turbine-generator shaft a...

It’s been known for many years that thermal temperature gradients across a rotor can alter the amplitude and phase of synchronous vibration. This is due to bowing of the shaft caused by a temperature difference between one side of the shaft and the other. The earliest published recognition of this phenomenon was by Newkirk [1], where the temperature difference was a result of frictional heating...