This paper presents the design optimization and characterization of a microscale, permanent-magnet (PM) generator, capable of supplying 8 W of dc power to a resistive load at a rotational speed of 305 000 rpm. The generator is a three-phase, axial-flux, PM machine, consisting of a stator with Cu surface windings and a multi-pole SmCo PM rotor. Optimization of the machine geometries has enabled ...

AIM To evaluate the effect of rotational speed and the angle and radius of curvature of root canals on the fracture of two types of nickel-titanium rotary instruments: K3 and ProTaper. METHODOLOGY A total of 240 root canals of extracted human maxillary and mandibular molars were divided into two groups of 120, according to the angle of the canal curvature (group A: <30 degrees, group B: >30 d...

Friction stir processing (FSP) was conducted on a SAF 2205 duplex stainless steel at advancing speed of 50 mm/min and rotational speed of 400 rpm.  Characterization of evolved material was studied using electron microscopy equipped with electron back scattered diffraction (EBSD) system. The results indicated that the severe plastic deformation and the heat generated during the FSP developed a v...

INTRODUCTION Optical trapping is a laser-based method for probing the physiological and mechanical properties of cells in a noninvasive manner. As sperm motility is an important criterion for assessing the male fertility potential, this technique is used to study sperm cell motility behavior and rotational dynamics. METHODS AND PATIENTS An integrated optical system with near-infrared laser be...

Abstract—Friction stir welding is a modern and an environmentally friendly solid state joining process used to joint relatively lighter family of materials. Recently, friction stir spot welding has been used instead of resistance spot welding which has received considerable attention from the automotive industry. It is environmentally friendly process that eliminated heat and pollution. In this...

This paper describes a method to measure and compensate a 4 axes ultra-precision machine tool that generates micro patterns on the large surfaces. The grooving machine is usually used for making a micro mold for many electrical parts such as a light guide plate for LCD and fuel cells. The ultra precision machine tool has three linear axes and one rotational table. Shaping is usually used to gen...

Abstract Friction stir welding is a solid state joining method used to join materials which cannot be joined by fusion welding. In this method, heat produced due the friction between tool and workpiece weld material. Heat input depends upon amount of caused process parameters such as rotational speed, geometry, axial force etc. present study, effect shoulder pin diameter ratio, speed on peak te...

A 1arge-scale tumble rather than swirl would exist in cylinders in the case of two valves’ opening in a fourvalve engine. A strong swirl is generated when one valve is closed, yet the flow capacity is less than that of two valves being opened. In order to change it, different lifts of valves (DLV) present are achieved. In the case of using different lifts of two intake valves, both tumble and s...

An asymmetric microgear will spontaneously and unidirectionally rotate if it is heated in a cool surrounding solvent. The resulting temperature gradient along the edges of the gear teeth translates in a directed thermophoretic force, which will exert a net torque on the gear. By means of computer simulations, the validity of this scenario is proved. The rotational direction and speed are depend...