Optical fiber tapers are used to collect photoluminescence emission at approximately 1.5 microm from photonic crystal cavities fabricated in erbium doped silicon nitride on silicon. In the experiment, photoluminescence collection via one arm of the fiber taper is enhanced 2.5 times relative to free space collection, corresponding to a net collection efficiency of 4%. Theoretically, the collecti...

A cascaded symmetrical dual-taper Mach-Zehnder interferometer structure based on guided-mode and leaky-mode interference is proposed in this paper. Firstly, the interference spectrum characteristics of interferometer has been analyzed by the Finite Difference-Beam Propagation Method (FD-BPM). When the diameter of taper waist is 20 μm-30 μm, dual-taper length is 1 mm and taper distance is 4 cm-6...

BACKGROUND Several studies have demonstrated a positive association between physical activity (PA) and health-related quality of life (HRQL). However, studies have suggested that this association depends both on the PA intensity and the domain of HRQL evaluated. This study aimed to explore the association between physical, mental and overall HRQL with recommended levels of PA. PA levels were di...

For a fiber optical surface plasmon resonance (SPR) sensor a short part of its cladding should be removed to coat a thin layer of a metal. Usually this is problematic when an optical fiber with small core diameter is used. In this paper, a new method using µliter droplet of the HF acid for short fiber optical taper fabrication is reported. Using this method in a multi-mode optical fiber w...

A nonuniform-shape photonic crystal taper integrated with a single-mode optical fiber and a photonic crystal waveguide for high-efficiency mode coupling is presented. The curvature of the tapering section is varied by the parameter alpha. For values of alpha set to 2 and 0.5, concave and convex tapers are obtained, respectively. Numerical calculations yield an average coupling efficiency greate...

A Nyquist filter can have any odd symmetric taper as a transition between its pass band and stop band. The most well known taper is the raised cosine (RC) taper specified in most communication standards. The square root (SRRC) Nyquist filter formed from this prototype exhibits high spectral side lobe levels that fail to meet severe spectral mask requirements. This paper presents a SR Nyquist fi...

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...

Recent healthcare legislation, financial pressures, and regulatory oversight have increased the need to create improved mechanisms for performance measurement, quality management tracking, and outcomesbased research. The Anesthesia Quality Institute (AQI) has established the National Anesthesia Clinical Outcomes Registry (NACOR) to support these requirements for a wide-range of customers includ...

Electromagnetic scattering is considered from finite and electrically large perfectly conducting rough surfaces. Three solution approaches are considered. The first two are based on a multi-level fast-multipole algorithm (MLFMA) formulation. In one MLFMA approach the rough surface resides in free space and is terminated by a resistive taper. In the second MLFMA approach the rough surface is ter...