We design and fabricate ultra-low-loss tapered optical fibers (TOFs) with minimal lengths. We first optimize variations of the torch scan length using the flame-brush method for fabricating TOFs with taper angles that satisfy the adiabaticity criteria. We accordingly fabricate TOFs with optimal shapes and compare their transmission to TOFs with a constant taper angle and TOFs with an exponentia...

introduction: the objective of this study was to compare the shaping ability of three rotary filing systems; constant taper k3 instruments, constant taper profile instruments and progressive taper protaper rotary instruments in clear resin blocks with simulated curved root canals. materials and methods: forty five resin blocks were divided into three groups. group a preparation was conducted wi...

We show that high-Q whispering-gallery modes in fused-silica microspheres can be efficiently excited by an optical fiber taper. By adjusting the taper diameter to match the ropagation constant of the mode in the taper with that of the resonant mode of interest, one can couple more than 90% of the light into the sphere. This represents a significant improvement in excitation efficiency compared ...

AIM To compare the shaping ability of progressive versus constant taper shaft instruments in curved root canals of extracted human teeth. METHODOLOGY A total of 40 root canals of mandibular molars with curvatures ranging between 20 degrees and 40 degrees were divided into two groups of 20 canals each and embedded in a muffle system. The root canals sectioned horizontally at three levels befor...

Vibrations of plate and plate type structures made up of composite materials have a significant role in various industrial mechanical structures, aerospace industries and other engineering applications. The main aim of the present paper is to study the two dimensional thermal effect on the vibration of non-homogeneous square plate of variable thickness having clamped boundary. It is assumed tha...

The aerodynamic drag reduction of road vehicles is continuing interest. arising from the rear surfaces usually dominant component, but this can be alleviated by tapering body. effects on characteristics a simple body adding an elongated tapered tail have been investigated in wind tunnel experiment. streamlined consists constant side taper added to upper taper. results compared with earlier stud...

INTRODUCTION The objective of this study was to compare the shaping ability of three rotary filing systems; constant taper K3 instruments, constant taper ProFile instruments and progressive taper ProTaper rotary instruments in clear resin blocks with simulated curved root canals. MATERIALS AND METHODS Forty five resin blocks were divided into three groups. Group A preparation was conducted wi...

The theoretical changes in shape and velocity of an action potential were computed in regions of changing core conductor geometry. Step decrease and step increase of diameter, branch points, and gradual taper or flare of diameter were studied. Results showed increase of both velocity and peak height as the action potential approaches a point of step decrease. A step increase causes decrease of ...